Tag Archives: quantum physics

Nanoscopic advance of colossal (!) significance by Danish quantum physicists

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it’s not often you see the word ‘colossal’ in a science news release but it seems these Danish researchers are very excited about their breakthrough. From a January 26, 2023 news item on Nanowerk,

In a new breakthrough, researchers at the University of Copenhagen, in collaboration with Ruhr University Bochum, have solved a problem that has caused quantum researchers headaches for years. The researchers can now control two quantum light sources rather than one. Trivial as it may seem to those uninitiated in quantum, this colossal breakthrough allows researchers to create a phenomenon known as quantum mechanical entanglement. This in turn, opens new doors for companies and others to exploit the technology commercially.

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A January 26, 2023 University of Copenhagen press release (also on EurekAlert), which originated the news item, provides context and more detail,

Going from one to two is a minor feat in most contexts. But in the world of quantum physics, doing so is crucial. For years, researchers around the world have strived to develop stable quantum light sources and achieve the phenomenon known as quantum mechanical entanglement – a phenomenon, with nearly sci-fi-like properties, where two light sources can affect each other instantly and potentially across large geographic distances. Entanglement is the very basis of quantum networks and central to the development of an efficient quantum computer.  

Today [January 26, 2023], researchers from the Niels Bohr Institute published a new result in the highly esteemed journal Science, in which they succeeded in doing just that. According to Professor Peter Lodahl, one of the researchers behind the result, it is a crucial step in the effort to take the development of quantum technology to the next level and to “quantize” society’s computers, encryption and the internet.

“We can now control two quantum light sources and connect them to each other. It might not sound like much, but it’s a major advancement and builds upon the past 20 years of work. By doing so, we’ve revealed the key to scaling up the technology, which is crucial for the most ground-breaking of quantum hardware applications,” says Professor Peter Lodahl, who has conducted research the area since 2001.  

The magic all happens in a so-called nanochip – which is not much larger than the diameter of a human hair – that the researchers also developed in recent years.

Quantum sources overtake the world’s most powerful computer 

Peter Lodahl’s group is working with a type of quantum technology that uses light particles, called photons, as micro transporters to move quantum information about.

While Lodahl’s group is a leader in this discipline of quantum physics, they have only been able to control one light source at a time until now. This is because light sources are extraordinarily sensitive to outside “noise”, making them very difficult to copy. In their new result, the research group succeeded in creating two identical quantum light sources rather than just one.

“Entanglement means that by controlling one light source, you immediately affect the other. This makes it possible to create a whole network of entangled quantum light sources, all of which interact with one another, and which you can get to perform quantum bit operations in the same way as bits in a regular computer, only much more powerfully,” explains postdoc Alexey Tiranov, the article’s lead author. 

This is because a quantum bit can be both a 1 and 0 at the same time, which results in processing power that is unattainable using today’s computer technology. According to Professor Lodahl, just 100 photons emitted from a single quantum light source will contain more information than the world’s largest supercomputer can process.

By using 20-30 entangled quantum light sources, there is the potential to build a universal error-corrected quantum computer – the ultimate “holy grail” for quantum technology, that large IT companies are now pumping many billions into.

Other actors will build upon the research

According to Lodahl, the biggest challenge has been to go from controlling one to two quantum light sources. Among other things, this has made it necessary for researchers to develop extremely quiet nanochips and have precise control over each light source.

With the new research breakthrough, the fundamental quantum physics research is now in place. Now it is time for other actors to take the researchers’ work and use it in their quests to deploy quantum physics in a range of technologies including computers, the internet and encryption.

“It is too expensive for a university to build a setup where we control 15-20 quantum light sources. So, now that we have contributed to understanding the fundamental quantum physics and taken the first step along the way, scaling up further is very much a technological task,” says Professor Lodahl.  

The research was conducted at the Danish National Research Foundation’s “Center of Excellence for Hybrid Quantum Networks (Hy-Q)” and is a collaboration between Ruhr University Bochum in Germany and the the University of Copenhagen’s Niels Bohr Institute.

Here’s a link to and a citation for this colossal research,

Collective super- and subradiant dynamics between distant optical quantum emitters by Alexey Tiranov, Vasiliki Angelopoulou, Cornelis Jacobus van Diepen, Björn Schrinski, Oliver August Dall’Alba Sandberg, Ying Wang, Leonardo Midolo, Sven Scholz, Andreas Dirk Wieck, Arne Ludwig, Anders Søndberg Sørensen, and Peter Lodahl. Science 26 Jan 2023 Vol 379, Issue 6630 pp. 389-393 DOI: 10.1126/science.ade9324

This paper is behind a paywall.

FrogHeart’s 2022 comes to an end as 2023 comes into view

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I look forward to 2023 and hope it will be as stimulating as 2022 proved to be. Here’s an overview of the year that was on this blog:

Sounds of science

It seems 2022 was the year that science discovered the importance of sound and the possibilities of data sonification. Neither is new but this year seemed to signal a surge of interest or maybe I just happened to stumble onto more of the stories than usual.

This is not an exhaustive list, you can check out my ‘Music’ category for more here. I have tried to include audio files with the postings but it all depends on how accessible the researchers have made them.

Aliens on earth: machinic biology and/or biological machinery?

When I first started following stories in 2008 (?) about technology or machinery being integrated with the human body, it was mostly about assistive technologies such as neuroprosthetics. You’ll find most of this year’s material in the ‘Human Enhancement’ category or you can search the tag ‘machine/flesh’.

However, the line between biology and machine became a bit more blurry for me this year. You can see what’s happening in the titles listed below (you may recognize the zenobot story; there was an earlier version of xenobots featured here in 2021):

This was the story that shook me,

Are the aliens going to come from outer space or are we becoming the aliens?

Brains (biological and otherwise), AI, & our latest age of anxiety

As we integrate machines into our bodies, including our brains, there are new issues to consider:

  • Going blind when your neural implant company flirts with bankruptcy (long read) April 5, 2022 posting
  • US National Academies Sept. 22-23, 2022 workshop on techno, legal & ethical issues of brain-machine interfaces (BMIs) September 21, 2022 posting

I hope the US National Academies issues a report on their “Brain-Machine and Related Neural Interface Technologies: Scientific, Technical, Ethical, and Regulatory Issues – A Workshop” for 2023.

Meanwhile the race to create brainlike computers continues and I have a number of posts which can be found under the category of ‘neuromorphic engineering’ or you can use these search terms ‘brainlike computing’ and ‘memristors’.

On the artificial intelligence (AI) side of things, I finally broke down and added an ‘artificial intelligence (AI) category to this blog sometime between May and August 2021. Previously, I had used the ‘robots’ category as a catchall. There are other stories but these ones feature public engagement and policy (btw, it’s a Canadian Science Policy Centre event), respectively,

  • “The “We are AI” series gives citizens a primer on AI” March 23, 2022 posting
  • “Age of AI and Big Data – Impact on Justice, Human Rights and Privacy Zoom event on September 28, 2022 at 12 – 1:30 pm EDT” September 16, 2022 posting

These stories feature problems, which aren’t new but seem to be getting more attention,

While there have been issues over AI, the arts, and creativity previously, this year they sprang into high relief. The list starts with my two-part review of the Vancouver Art Gallery’s AI show; I share most of my concerns in part two. The third post covers intellectual property issues (mostly visual arts but literary arts get a nod too). The fourth post upends the discussion,

  • “Mad, bad, and dangerous to know? Artificial Intelligence at the Vancouver (Canada) Art Gallery (1 of 2): The Objects” July 28, 2022 posting
  • “Mad, bad, and dangerous to know? Artificial Intelligence at the Vancouver (Canada) Art Gallery (2 of 2): Meditations” July 28, 2022 posting
  • “AI (artificial intelligence) and art ethics: a debate + a Botto (AI artist) October 2022 exhibition in the Uk” October 24, 2022 posting
  • Should AI algorithms get patents for their inventions and is anyone talking about copyright for texts written by AI algorithms? August 30, 2022 posting

Interestingly, most of the concerns seem to be coming from the visual and literary arts communities; I haven’t come across major concerns from the music community. (The curious can check out Vancouver’s Metacreation Lab for Artificial Intelligence [located on a Simon Fraser University campus]. I haven’t seen any cautionary or warning essays there; it’s run by an AI and creativity enthusiast [professor Philippe Pasquier]. The dominant but not sole focus is art, i.e., music and AI.)

There is a ‘new kid on the block’ which has been attracting a lot of attention this month. If you’re curious about the latest and greatest AI anxiety,

  • Peter Csathy’s December 21, 2022 Yahoo News article (originally published in The WRAP) makes this proclamation in the headline “Chat GPT Proves That AI Could Be a Major Threat to Hollywood Creatives – and Not Just Below the Line | PRO Insight”
  • Mouhamad Rachini’s December 15, 2022 article for the Canadian Broadcasting Corporation’s (CBC) online news overs a more generalized overview of the ‘new kid’ along with an embedded CBC Radio file which runs approximately 19 mins. 30 secs. It’s titled “ChatGPT a ‘landmark event’ for AI, but what does it mean for the future of human labour and disinformation?” The chat bot’s developer, OpenAI, has been mentioned here many times including the previously listed July 28, 2022 posting (part two of the VAG review) and the October 24, 2022 posting.

Opposite world (quantum physics in Canada)

Quantum computing made more of an impact here (my blog) than usual. it started in 2021 with the announcement of a National Quantum Strategy in the Canadian federal government budget for that year and gained some momentum in 2022:

  • “Quantum Mechanics & Gravity conference (August 15 – 19, 2022) launches Vancouver (Canada)-based Quantum Gravity Institute and more” July 26, 2022 posting Note: This turned into one of my ‘in depth’ pieces where I comment on the ‘Canadian quantum scene’ and highlight the appointment of an expert panel for the Council of Canada Academies’ report on Quantum Technologies.
  • “Bank of Canada and Multiverse Computing model complex networks & cryptocurrencies with quantum computing” July 25, 2022 posting
  • “Canada, quantum technology, and a public relations campaign?” December 29, 2022 posting

This one was a bit of a puzzle with regard to placement in this end-of-year review, it’s quantum but it’s also about brainlike computing

It’s getting hot in here

Fusion energy made some news this year.

There’s a Vancouver area company, General Fusion, highlighted in both postings and the October posting includes an embedded video of Canadian-born rapper Baba Brinkman’s “You Must LENR” [L ow E nergy N uclear R eactions or sometimes L attice E nabled N anoscale R eactions or Cold Fusion or CANR (C hemically A ssisted N uclear R eactions)].

BTW, fusion energy can generate temperatures up to 150 million degrees Celsius.

Ukraine, science, war, and unintended consequences

Here’s what you might expect,

These are the unintended consequences (from Rachel Kyte’s, Dean of the Fletcher School, Tufts University, December 26, 2022 essay on The Conversation [h/t December 27, 2022 news item on phys.org]), Note: Links have been removed,

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Russian President Vladimir Putin’s war on Ukraine has reverberated through Europe and spread to other countries that have long been dependent on the region for natural gas. But while oil-producing countries and gas lobbyists are arguing for more drilling, global energy investments reflect a quickening transition to cleaner energy. [emphasis mine]

Call it the Putin effect – Russia’s war is speeding up the global shift away from fossil fuels.

In December [2022?], the International Energy Agency [IEA] published two important reports that point to the future of renewable energy.

First, the IEA revised its projection of renewable energy growth upward by 30%. It now expects the world to install as much solar and wind power in the next five years as it installed in the past 50 years.

The second report showed that energy use is becoming more efficient globally, with efficiency increasing by about 2% per year. As energy analyst Kingsmill Bond at the energy research group RMI noted, the two reports together suggest that fossil fuel demand may have peaked. While some low-income countries have been eager for deals to tap their fossil fuel resources, the IEA warns that new fossil fuel production risks becoming stranded, or uneconomic, in the next 20 years.

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Kyte’s essay is not all ‘sweetness and light’ but it does provide a little optimism.

Kudos, nanotechnology, culture (pop & otherwise), fun, and a farewell in 2022

This one was a surprise for me,

Sometimes I like to know where the money comes from and I was delighted to learn of the Ărramăt Project funded through the federal government’s New Frontiers in Research Fund (NFRF). Here’s more about the Ărramăt Project from the February 14, 2022 posting,

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“The Ărramăt Project is about respecting the inherent dignity and interconnectedness of peoples and Mother Earth, life and livelihood, identity and expression, biodiversity and sustainability, and stewardship and well-being. Arramăt is a word from the Tamasheq language spoken by the Tuareg people of the Sahel and Sahara regions which reflects this holistic worldview.” (Mariam Wallet Aboubakrine)

Over 150 Indigenous organizations, universities, and other partners will work together to highlight the complex problems of biodiversity loss and its implications for health and well-being. The project Team will take a broad approach and be inclusive of many different worldviews and methods for research (i.e., intersectionality, interdisciplinary, transdisciplinary). Activities will occur in 70 different kinds of ecosystems that are also spiritually, culturally, and economically important to Indigenous Peoples.

The project is led by Indigenous scholars and activists …

Kudos to the federal government and all those involved in the Salmon science camps, the Ărramăt Project, and other NFRF projects.

There are many other nanotechnology posts here but this appeals to my need for something lighter at this point,

  • “Say goodbye to crunchy (ice crystal-laden) in ice cream thanks to cellulose nanocrystals (CNC)” August 22, 2022 posting

The following posts tend to be culture-related, high and/or low but always with a science/nanotechnology edge,

Sadly, it looks like 2022 is the last year that Ada Lovelace Day is to be celebrated.

… this year’s Ada Lovelace Day is the final such event due to lack of financial backing. Suw Charman-Anderson told the BBC [British Broadcasting Corporation] the reason it was now coming to an end was:

You can read more about it here:

In the rearview mirror

A few things that didn’t fit under the previous heads but stood out for me this year. Science podcasts, which were a big feature in 2021, also proliferated in 2022. I think they might have peaked and now (in 2023) we’ll see what survives.

Nanotechnology, the main subject on this blog, continues to be investigated and increasingly integrated into products. You can search the ‘nanotechnology’ category here for posts of interest something I just tried. It surprises even me (I should know better) how broadly nanotechnology is researched and applied.

If you want a nice tidy list, Hamish Johnston in a December 29, 2022 posting on the Physics World Materials blog has this “Materials and nanotechnology: our favourite research in 2022,” Note: Links have been removed,

“Inherited nanobionics” makes its debut

The integration of nanomaterials with living organisms is a hot topic, which is why this research on “inherited nanobionics” is on our list. Ardemis Boghossian at EPFL [École polytechnique fédérale de Lausanne] in Switzerland and colleagues have shown that certain bacteria will take up single-walled carbon nanotubes (SWCNTs). What is more, when the bacteria cells split, the SWCNTs are distributed amongst the daughter cells. The team also found that bacteria containing SWCNTs produce a significantly more electricity when illuminated with light than do bacteria without nanotubes. As a result, the technique could be used to grow living solar cells, which as well as generating clean energy, also have a negative carbon footprint when it comes to manufacturing.

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Getting to back to Canada, I’m finding Saskatchewan featured more prominently here. They do a good job of promoting their science, especially the folks at the Canadian Light Source (CLS), Canada’s synchrotron, in Saskatoon. Canadian live science outreach events seeming to be coming back (slowly). Cautious organizers (who have a few dollars to spare) are also enthusiastic about hybrid events which combine online and live outreach.

After what seems like a long pause, I’m stumbling across more international news, e.g. “Nigeria and its nanotechnology research” published December 19, 2022 and “China and nanotechnology” published September 6, 2022. I think there’s also an Iran piece here somewhere.

With that …

Making resolutions in the dark

Hopefully this year I will catch up with the Council of Canadian Academies (CCA) output and finally review a few of their 2021 reports such as Leaps and Boundaries; a report on artificial intelligence applied to science inquiry and, perhaps, Powering Discovery; a report on research funding and Natural Sciences and Engineering Research Council of Canada.

Given what appears to a renewed campaign to have germline editing (gene editing which affects all of your descendants) approved in Canada, I might even reach back to a late 2020 CCA report, Research to Reality; somatic gene and engineered cell therapies. it’s not the same as germline editing but gene editing exists on a continuum.

For anyone who wants to see the CCA reports for themselves they can be found here (both in progress and completed).

I’m also going to be paying more attention to how public relations and special interests influence what science is covered and how it’s covered. In doing this 2022 roundup, I noticed that I featured an overview of fusion energy not long before the breakthrough. Indirect influence on this blog?

My post was precipitated by an article by Alex Pasternak in Fast Company. I’m wondering what precipitated Alex Pasternack’s interest in fusion energy since his self-description on the Huffington Post website states this “… focus on the intersections of science, technology, media, politics, and culture. My writing about those and other topics—transportation, design, media, architecture, environment, psychology, art, music … .”

He might simply have received a press release that stimulated his imagination and/or been approached by a communications specialist or publicists with an idea. There’s a reason for why there are so many public relations/media relations jobs and agencies.

Que sera, sera (Whatever will be, will be)

I can confidently predict that 2023 has some surprises in store. I can also confidently predict that the European Union’s big research projects (1B Euros each in funding for the Graphene Flagship and Human Brain Project over a ten year period) will sunset in 2023, ten years after they were first announced in 2013. Unless, the powers that be extend the funding past 2023.

I expect the Canadian quantum community to provide more fodder for me in the form of a 2023 report on Quantum Technologies from the Council of Canadian academies, if nothing else otherwise.

I’ve already featured these 2023 science events but just in case you missed them,

  • 2023 Preview: Bill Nye the Science Guy’s live show and Marvel Avengers S.T.A.T.I.O.N. (Scientific Training And Tactical Intelligence Operative Network) coming to Vancouver (Canada) November 24, 2022 posting
  • September 2023: Auckland, Aotearoa New Zealand set to welcome women in STEM (science, technology, engineering, and mathematics) November 15, 2022 posting

Getting back to this blog, it may not seem like a new year during the first few weeks of 2023 as I have quite the stockpile of draft posts. At this point I have drafts that are dated from June 2022 and expect to be burning through them so as not to fall further behind but will be interspersing them, occasionally, with more current posts.

Most importantly: a big thank you to everyone who drops by and reads (and sometimes even comments) on my posts!!! it’s very much appreciated and on that note: I wish you all the best for 2023.

Canada, quantum technology, and a public relations campaign?

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Stephanie Simmons’ October 31, 2022 essay on quantum technology and Canada for The Conversation (h/t Nov.1.22 news item on phys.org) was a bit startling—not due to the content—but for the chosen communications vehicle. It’s the kind of piece i expect to find in the Globe and Mail or the National Post not The Conversation, which aspires to present in depth, accessible academic research and informed news stories (or so I thought). (See The Conversation (website) Wikipedia entry for more.)

Simmons (who is an academic) seems to have ‘written’ a run-of-the-mill public relations piece (with a good and accessible description of quantum encryption and its future importance) about Canada and quantum technology aimed at influencing government policy makers while using some magic words (Note: Links have been removed),

Canada is a world leader in developing quantum technologies and is well-positioned to secure its place in the emerging quantum industry.

Quantum technologies are new and emerging technologies based on the unique properties of quantum mechanics — the science that deals with the physical properties of nature on an atomic and subatomic level.

In the future, we’ll see quantum technology transforming computing, communications, cryptography and much more. They will be incredibly powerful, offering capabilities that reach beyond today’s technologies.

The potential impact of these technologies on the Canadian economy [emphasis mine] will be transformative: the National Research Council of Canada has identified quantum technology as a $142 billion opportunity that could employ 229,000 Canadians by 2040 [emphasis mine].

Canada could gain far-reaching economic and social benefits from the rapidly developing quantum industry, but it must act now to secure them — before someone else [emphasis mine] delivers the first large-scale quantum computer, which will likely be sooner than expected.

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This is standard stuff, any professional business writer, after a little research, could have pulled the article together. But, it’s Stephanie Simmons whose academic titles (Associate Professor, SFU and Tier 2 Canada Research Chair in Silicon Quantum Technologies, Simon Fraser University) and position as founder and Chief Quantum Officer of Photonic, Inc. give her comments added weight. (For an academic, this is an unusual writing style [perhaps Simmons had some help?] and it better belongs in the newspapers I’ve previously cited.)

Simmons, having stoked a little anxiety with “it [Canada] must act now to secure them [economic and social benefits] — before someone else delivers the first large-scale quantum computer, which will likely be sooner than expected,” gets to her main points, from the October 31, 2022 essay,

To maintain its leadership, Canada needs to move beyond research and development and accelerate a quantum ecosystem that includes a strong talent pipeline, businesses supported by supply chains and governments and industry involvement. There are a few things Canada can do to drive this leadership:

Continue to fund quantum research: … The Canadian government has invested more than $1 billion since 2005 in quantum research and will likely announce a national quantum strategy soon [emphasis mine]. Canada must continue funding quantum research or risk losing its talent base and current competitive advantage. [Note: Canada has announced a national quantum strategy in both the 2021 and 2022 federal budgets See more under the ‘Don’t we already have a national quantum strategy? subhead]

Build our talent pipeline with more open immigration: …

Be our own best customers: Canadian companies are leading the way, but they need support [emphasis mine; by support, does she mean money?]. Quantum Industry Canada boasts of more than 30 member companies. Vancouver is home to the pioneering D-Wave and Photonic Inc., …

As noted in a previous post (July 26, 2022 titled “Quantum Mechanics & Gravity conference [August 15 – 19, 2022] launches Vancouver (Canada)-based Quantum Gravity Institute and more”), all of this enthusiasm tends to come down to money, as in, ‘We will make money which will somehow benefit you but, first, we need more money from you’. As for the exhortation to loosen up immigration, that sounds like an attempt to exacerbate ‘brain drain’, i.e., lure people from other countries to settle in Canada. As a country whose brains were drained in the 1960s, 70s, etc., it should be noted those drives were deeply resented here and I expect that we will become objects of resentment should we resort to the same tactics although I thought we already had.

Same anxieties, same solution

Simmons concludes with a cautionary tale, from the October 31, 2022 essay, Note: Links have been removed,

Canada has an opportunity to break out of its pattern of inventing transformative technology, but not reaping the rewards. This is what happened with the invention of the transistor.

The first transistor patent was actually filed in Canada by Canadian-Hungarian physicist Julius Edgar Lilienfeld, 20 years before the Bell Labs demonstration. Canada was also one of the places where Alexander Graham Bell worked to develop and patent the telephone.

Despite this, the transistor was commercialized in the U.S. and led to the country’s US$63 billion semiconductor industry. Bell commercialized the telephone through The Bell Telephone Company, which eventually became AT&T.

Canada is poised to make even greater contributions to quantum technology. Much existing technology has been invented here in Canada — including quantum cryptography, which was co-invented by University of Montreal professor Gilles Brassard. Instead of repeating its past mistakes, Canada should act now to secure the success of the quantum technology industry.

I bought into this narrative too. It’s compelling and generally accepted (in short, it’s a part of Canadian culture) but somebody who’s smarter about business and economics than I am pointed out that Canada has a good standard of living and has had that standard for many years despite decades of worry over our ‘inability’ to commercialize our discoveries. Following on that thought, what’s so bad about our situation? Are we behind because we don’t have a huge semiconductor industry? I don’t know but perhaps we need to question this narrative a little more closely. Where some people see loss, others might see agility, inventiveness, and the ability to keep capitalizing on early stage technology, over and over again.

What I haven’t yet seen discussed as a problem is a Canadian culture that encourages technology entrepreneurs to create startups with the intention of selling them to a big US (or other country) corporation. I’m most familiar with the situation in the province of British Columbia where a 2003 British Columbia Techmap (developed by the accounting firm PriceWaterhouseCoopers [PWC]) provides a genealogy which stretched from the 1890s to 2003. The number of technology companies acquired by foreign corporations is astonishing. Our technology has been bought—over and over, since the 1890s.

(I believe there were three editions of the British Columbia Techmap: 1997, 2003 and 2012. PWC seems to have discontinued publication and the 2012 online edition is no longer available. For the curious, there’s a June 15, 2012 announcement, which provides a little information about and interesting facts from the 2012 digital edition.)

This ‘startup and sell’ story holds true at the national level as well. We have some large technology companies but none of them compare to these: Huawei (China), Ali Baba (China), Intel (US), Apple (US), Siemens (Germany), Sanofi (France; technically a pharmaceutical but heavily invested in technology), etc.

So, is this “… inventing transformative technology, but not reaping the rewards …” really a problem when Canadians live well? If so, we need to change our entrepreneurial and business culture.

Don’t we already have a national quantum strategy?

It’s a little puzzling to see Simmons appear to be arguing for a national quantum strategy given this (from my July 26, 2022 posting),

A National Quantum Strategy was first announced in the 2021 Canadian federal budget and reannounced in the 2022 federal budget (see my April 19, 2022 posting for a few more budget details).. Or, you may find this National Quantum Strategy Consultations: What We Heard Report more informative. There’s also a webpage for general information about the National Quantum Strategy.

As evidence of action, the Natural Science and Engineering Research Council of Canada (NSERC) announced new grant programmes made possible by the National Quantum Strategy in a March 15, 2022 news release,

Quantum science and innovation are giving rise to promising advances in communications, computing, materials, sensing, health care, navigation and other key areas. The Government of Canada is committed to helping shape the future of quantum technology by supporting Canada’s quantum sector and establishing leadership in this emerging and transformative domain.

Today [March 15, 2022], the Honourable François-Philippe Champagne, Minister of Innovation, Science and Industry, is announcing an investment of $137.9 million through the Natural Sciences and Engineering Research Council of Canada’s (NSERC) Collaborative Research and Training Experience (CREATE) grants and Alliance grants. These grants are an important next step in advancing the National Quantum Strategy and will reinforce Canada’s research strengths in quantum science while also helping to develop a talent pipeline to support the growth of a strong quantum community.

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it gets even more puzzling when you know that Simmons is part of a Canadian Council of Academies (CCA) expert panel (announced in May 2022) to produce a report on Quantum Technologies,

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Budget 2021 included a National Quantum Strategy [emphasis mine] to amplify Canada’s strength in quantum research, grow quantum-ready technologies, and solidify Canada’s global leadership in this area. A comprehensive exploration of the capabilities and potential vulnerabilities of these technologies will help to inform their future deployment across the society and the economy.

This assessment will examine the impacts, opportunities, and challenges quantum technologies present for industry, governments, and people in Canada. [emphases mine]

The Sponsor:

National Research Council Canada and Innovation, Science and Economic Development Canada [emphasis mine]

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It’s possible someone else wrote the essay, someone who doesn’t know about the strategy or Simmons’ involvement in a CCA report on how to address the issues highlighted in her October 31, 2022 essay. It’s also possible that Simmons is trying to emphasize the need for a commercialization strategy for quantum technologies.

Given that the Council of Canadian Academies (CCA) was asked to produce what looks like a comprehensive national strategy including commercialization, I prefer the second possibility.

*ETA December 29, 2022 1020 hours PT: On a purely speculative note, I just noticed involvement from a US PR agency in this project, from my “Bank of Canada and Multiverse Computing model complex networks & cryptocurrencies with quantum computing” July 25, 2022 posting,

As for the company that produced the news release, HKA Marketing Communications, based in Southern California, they claim this “Specialists in Quantum Tech PR: #1 agency in this space” on their homepage.

Simmons is on the CCA’s Quantum Technologies’ expert panel along with Eric Santor, Advisor to the Governor, Bank of Canada. HKA’s involvement would certainly explain why the writer didn’t know there’s already a National Quantum Strategy and not know about Simmons’ membership in the expert panel. As I noted, this is pure speculation; I have no proof.*

At any rate, there may be another problem, our national quantum dilemma may be due to difficulties within the Canadian quantum community.

A fractious Canadian quantum community

I commented on the competitiveness within the quantum technologies community in my May 4, 2021 posting about the federal 2021 budget, “While the folks in the quantum world are more obviously competitive … ,” i.e., they are strikingly public in comparison to the genomic and artificial intelligence communities. Scroll down to the ‘National Quantum Strategy’ subhead in the May 4, 2021 posting for an example.

It can also be seen in my July 26, 2022 posting about the Vancouver (Canada) launch of the Quantum Gravity Institute where I noted the lack of Canadian physicists (not one from the CCA expert panel, the Perimeter Institute, or TRIUMF; Canada’s particle accelerator centre, or the Institute for Quantum Computing at the University of Waterloo) in the speaker list and the prominent role wealthy men who’ve taken up quantum science as a hobby played in its founding. BTW, it seems two Canadian physicists (in addition to Philip Stamp; all from the University of British Columbia) were added to the speaker list and D-Wave Systems was added to the institute’s/conference’s webpage sponsorship list (scroll down about 70% of the way) after I posted.

Hopefully the quantum science/research community will pull together, in public, at least.

Who is the audience?

Getting back to Simmons’ piece on The Conversation, her essay, especially one that appears to be part of a public relations campaign, can appeal to more than one audience. The trick, as all (script, news, business, public relations, science, etc.) writers will tell you, is to write for one audience. As counter-intuitive as that trick may seem, it works.

Canadian policy makers should already know that the federal government has announced a national quantum strategy in two different budgets. Additionally, affected scientists should already know about the national strategy, such as it is. Clearly, children are not the intended audience. Perhaps it’s intended for a business audience but the specific business case is quite weak and, as I’ve noted here and elsewhere, the ‘failure’ to take advantage of early developments is a well worn science business trope which ignores a Canadian business model focused on developing emerging technology then, selling it.

This leaves a ‘general’ audience as the only one left and that audience doesn’t tend to read The Conversation website. Here’s the description of the publisher from its Wikipedia entry, Note: Links have been removed,

The Conversation is a network of not-for-profit media outlets publishing news stories and research reports online, with accompanying expert opinion and analysis.[1][2] Articles are written by academics and researchers [emphasis mine]under a free Creative Commons license, allowing reuse without modification.[3][2] Its model has been described as explanatory journalism.[4][5][6] [emphasis mine] Except in “exceptional circumstances”, it only publishes articles by “academics employed by, or otherwise formally connected to, accredited institutions, including universities and accredited research bodies”.[7]: 8 

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Simmons’ piece is not so much explanatory as it is a plea for a policy on a website that newspapers use for free, pre-edited, and proofed content.

I imagine the hope was that a Canadian national newspaper such as the Globe & Mail and/or the National Post would republish it. That hope was realized when the National Post and, unexpectedly, a local paper, the Winnipeg Free Press, both republished it on November 1, 2022.

To sum up, it’s not clear to me what the goal for this piece was. Government policy makers don’t need it, the business case is not sufficiently supported, children are not going to care, and affected scientists are already aware of the situation. (Scientists who will be not affected by a national quantum policy will have their own agendas.) As for a member of the general audience, am I supposed to do something … other than care, that is?

The meaning of a banana

It is an odd piece which may or may not be part of a larger public relations campaign.

As a standalone piece, it reiterates the age old message regarding Canadian technology (“we don’t do a good job of commercializing our technology) to no great avail. As part of a strategy, it seems to be a misfire since we already have a national quantum strategy and Simmons is working on an expert panel that should be delivering the kind of policy she’s requesting.

In the end, all that can be said for certain is that Stephanie Simmons’ October 31, 2022 essay on quantum technology and Canada was published in The Conversation then republished elsewhere.

As Freud may or may not have said, “Sometimes a banana is just a banana.”

2022 Nobel Prize for Physics winners proved the existence of quantum entanglement

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In early October 2022, Alain Aspect, John Clauser and Anton Zeilinger were jointly awarded the 2022 Nobel Prize in Physics for work each scientist performed independently of the others.

Here’s more about the scientists and their works from an October 4, 2022 Nobel Prize press release,

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics 2022 to

Alain Aspect
Institut d’Optique Graduate School – Université Paris-
Saclay and École Polytechnique, Palaiseau, France

John F. Clauser
J.F. Clauser & Assoc., Walnut Creek, CA, USA

Anton Zeilinger
University of Vienna, Austria

“for experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science”

Entangled states – from theory to technology

Alain Aspect, John Clauser and Anton Zeilinger have each conducted groundbreaking experiments using entangled quantum states, where two particles behave like a single unit even when they are separated. Their results have cleared the way for new technology based upon quantum information.

The ineffable effects of quantum mechanics are starting to find applications. There is now a large field of research that includes quantum computers, quantum networks and secure quantum encrypted communication.

One key factor in this development is how quantum mechanics allows two or more particles to exist in what is called an entangled state. What happens to one of the particles in an entangled pair determines what happens to the other particle, even if they are far apart.

For a long time, the question was whether the correlation was because the particles in an entangled pair contained hidden variables, instructions that tell them which result they should give in an experiment. In the 1960s, John Stewart Bell developed the mathematical inequality that is named after him. This states that if there are hidden variables, the correlation between the results of a large number of measurements will never exceed a certain value. However, quantum mechanics predicts that a certain type of experiment will violate Bell’s inequality, thus resulting in a stronger correlation than would otherwise be possible.

John Clauser developed John Bell’s ideas, leading to a practical experiment. When he took the measurements, they supported quantum mechanics by clearly violating a Bell inequality. This means that quantum mechanics cannot be replaced by a theory that uses hidden variables.

Some loopholes remained after John Clauser’s experiment. Alain Aspect developed the setup, using it in a way that closed an important loophole. He was able to switch the measurement settings after an entangled pair had left its source, so the setting that existed when they were emitted could not affect the result.

Using refined tools and long series of experiments, Anton Zeilinger started to use entangled quantum states. Among other things, his research group has demonstrated a phenomenon called quantum teleportation, which makes it possible to move a quantum state from one particle to one at a distance.

“It has become increasingly clear that a new kind of quantum technology is emerging. We can see that the laureates’ work with entangled states is of great importance, even beyond the fundamental questions about the interpretation of quantum mechanics,”says Anders Irbäck, Chair of the Nobel Committee for Physics.

There are some practical applications for their work on establishing quantum entanglement as Dr. Nicholas Peters, University of Tennessee and Oak Ridge National Laboratory (ORNL), explains in his October 7, 2022 essay for The Conversation,

Unhackable communications devices, high-precision GPS and high-resolution medical imaging all have something in common. These technologies—some under development and some already on the market all rely on the non-intuitive quantum phenomenon of entanglement.

Two quantum particles, like pairs of atoms or photons, can become entangled. That means a property of one particle is linked to a property of the other, and a change to one particle instantly affects the other particle, regardless of how far apart they are. This correlation is a key resource in quantum information technologies.

For the most part, quantum entanglement is still a subject of physics research, but it’s also a component of commercially available technologies, and it plays a starring role in the emerging quantum information processing industry.

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Quantum entanglement is a critical element of quantum information processing, and photonic entanglement of the type pioneered by the Nobel laureates is crucial for transmitting quantum information. Quantum entanglement can be used to build large-scale quantum communications networks.

On a path toward long-distance quantum networks, Jian-Wei Pan, one of Zeilinger’s former students, and colleagues demonstrated entanglement distribution to two locations separated by 764 miles (1,203 km) on Earth via satellite transmission. However, direct transmission rates of quantum information are limited due to loss, meaning too many photons get absorbed by matter in transit so not enough reach the destination.

Entanglement is critical for solving this roadblock, through the nascent technology of quantum repeaters. An important milestone for early quantum repeaters, called entanglement swapping, was demonstrated by Zeilinger and colleagues in 1998. Entanglement swapping links one each of two pairs of entangled photons, thereby entangling the two initially independent photons, which can be far apart from each other.

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Perhaps the most well known quantum communications application is Quantum Key Distribution (QKD), which allows someone to securely distribute encryption keys. If those keys are stored properly, they will be secure, even from future powerful, code-breaking quantum computers.

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I don’t usually embed videos that are longer than 5 mins. but this one has a good explanation of cryptography (both classical and quantum),

The video host, Physics Girl (website), is also known as Dianna Cowern.

If you have the time, do read Peters’s October 7, 2022 essay, which can also be found as an October 10, 2022 news item on phys.org.

I wonder if there’s going to be a rush to fund and commercialize more quantum physics projects. There’s certainly an upsurge in activity locally and in Canada (I assume the same is true elsewhere) as my July 26, 2022 posting “Quantum Mechanics & Gravity conference (August 15 – 19, 2022) launches Vancouver (Canada)-based Quantum Gravity Institute and more” makes clear.

Celebrate World Quantum Day (April 14, 2022) with Conversations at the Perimeter

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Canada’s Perimeter Institute Institute for Theoretical Physics (PI) is launching a podcast, Conversations from the Perimeter, on World Quantum Day (April 14, 2022).

Here are some details from an April 7, 2022 PI news release (a shortened version was received via email),

Get to know some of the brilliant minds trying to solve nature’s deepest mysteries.

In 2020, our long-running public lecture series evolved to deliver the same cutting-edge physics talks in a virtual webcast format. Now, we’re excited to launch the next evolution in the series.

Starting next week, [April 14, 2022] Conversations at the Perimeter will take you into the depths of dark matter, black holes, and beyond as we introduce you to researchers working at the forefront of science.

The series is co-hosted by quantum physicist and lecturer Lauren Hayward and journalist-turned-science communicator Colin Hunter. In each episode, they chat with a guest scientist about their research, their motivations, the challenges they encounter, and the drive that keeps them searching for answers. 

Conversations at the Perimeter is the next evolution in Perimeter Institute’s long-running public lecture series, which changed in 2020 (like so much else) when in-person lectures became impossible. The new format allows Perimeter to showcase brilliant scientists and their ideas in a way that is interactive, lively, and safe. 

As always, the talks will be freely available on Perimeter’s YouTube channel – and, for the first time, they’ll be available via podcast, on all the major podcast channels. 

The first season will consist of 10 episodes, released every Thursday beginning on April 14 [2022] (World Quantum Day). Season one guests include loop quantum gravity founder Carlo Rovelli, theoretical cosmologist (and social media star) Katie Mack, quantum information scientist Raymond Laflamme, and more!

Happy world Quantum Day!

The Quantum Physicist as Causal Detective: an Oct. 7, 2020 event

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I love mysteries and am quite interested in the nature of reality (you, too?) and that gives us something in common with a couple of Perimeter Institute for Theoretical Physics (PI; Canada) researchers. From The Quantum Physicist as Causal Detective event page on the insidetheperimeter.ca website (notice received via email),

In their live webcast from Perimeter on October 7 [2020], Robert Spekkens and Elie Wolfe will shed light on the exciting possibilities brought about by applying quantum thinking to the science of cause and effect.

Watch the live webcast on this page on Wednesday, October 7 [2020] at 7 pm ET.

What do data science and the foundations of quantum theory have to do with one another?

A great deal, it turns out. The particular branch of data science known as causal inference focuses on a problem which is central to disciplines ranging from epidemiology to economics: that of disentangling correlation and causation in statistical data.

Meanwhile, in a slightly different guise, this same problem has been pondered by quantum physicists as part of a continuing effort to make sense of various puzzling quantum phenomena. On top of that, the most celebrated result concerning quantum theory’s meaning for the nature of reality – Bell’s theorem – can be seen in retrospect to be built on the solution to a particularly challenging problem in causal inference.

Recent efforts to elaborate upon these connections have led to an exciting flow of techniques and insights across the disciplinary divide.

Perimeter researchers Robert Spekkens and Elie Wolfe have done pioneering work studying relations of cause and effect through a quantum foundational lens, and can be counted among a small number of physicists worldwide with expertise in this field.

In their joint webcast from Perimeter [at 7 pm ET] on October 7 [2020], Spekkens and Wolfe will explore what is happening at the intersection of these two fields and how thinking like a quantum physicist leads to new ways of sussing out cause and effect from correlation patterns in statistical data.

For those of us on the West Coast, that webcast will be at 4 p.m. on Wednesday, Oct. 7, 2020 and I believe you can watch it here.

Quantum supremacy

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This supremacy, refers to an engineering milestone and a October 23, 2019 news item on ScienceDaily announces the milestone has been reached,

Researchers in UC [University of California] Santa Barbara/Google scientist John Martinis’ group have made good on their claim to quantum supremacy. Using 53 entangled quantum bits (“qubits”), their Sycamore computer has taken on — and solved — a problem considered intractable for classical computers.

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An October 23, 2019 UC Santa Barbara news release (also on EurekAlert) by Sonia Fernandez, which originated the news item, delves further into the work,

“A computation that would take 10,000 years on a classical supercomputer took 200 seconds on our quantum computer,” said Brooks Foxen, a graduate student researcher in the Martinis Group. “It is likely that the classical simulation time, currently estimated at 10,000 years, will be reduced by improved classical hardware and algorithms, but, since we are currently 1.5 trillion times faster, we feel comfortable laying claim to this achievement.”

The feat is outlined in a paper in the journal Nature.

The milestone comes after roughly two decades of quantum computing research conducted by Martinis and his group, from the development of a single superconducting qubit to systems including architectures of 72 and, with Sycamore, 54 qubits (one didn’t perform) that take advantage of the both awe-inspiring and bizarre properties of quantum mechanics.

“The algorithm was chosen to emphasize the strengths of the quantum computer by leveraging the natural dynamics of the device,” said Ben Chiaro, another graduate student researcher in the Martinis Group. That is, the researchers wanted to test the computer’s ability to hold and rapidly manipulate a vast amount of complex, unstructured data.

“We basically wanted to produce an entangled state involving all of our qubits as quickly as we can,” Foxen said, “and so we settled on a sequence of operations that produced a complicated superposition state that, when measured, returns bitstring with a probability determined by the specific sequence of operations used to prepare that particular superposition. The exercise, which was to verify that the circuit’s output correspond to the equence used to prepare the state, sampled the quantum circuit a million times in just a few minutes, exploring all possibilities — before the system could lose its quantum coherence.

‘A complex superposition state’

“We performed a fixed set of operations that entangles 53 qubits into a complex superposition state,” Chiaro explained. “This superposition state encodes the probability distribution. For the quantum computer, preparing this superposition state is accomplished by applying a sequence of tens of control pulses to each qubit in a matter of microseconds. We can prepare and then sample from this distribution by measuring the qubits a million times in 200 seconds.”

“For classical computers, it is much more difficult to compute the outcome of these operations because it requires computing the probability of being in any one of the 2^53 possible states, where the 53 comes from the number of qubits — the exponential scaling is why people are interested in quantum computing to begin with,” Foxen said. “This is done by matrix multiplication, which is expensive for classical computers as the matrices become large.”

According to the new paper, the researchers used a method called cross-entropy benchmarking to compare the quantum circuit’s output (a “bitstring”) to its “corresponding ideal probability computed via simulation on a classical computer” to ascertain that the quantum computer was working correctly.

“We made a lot of design choices in the development of our processor that are really advantageous,” said Chiaro. Among these advantages, he said, are the ability to experimentally tune the parameters of the individual qubits as well as their interactions.

While the experiment was chosen as a proof-of-concept for the computer, the research has resulted in a very real and valuable tool: a certified random number generator. Useful in a variety of fields, random numbers can ensure that encrypted keys can’t be guessed, or that a sample from a larger population is truly representative, leading to optimal solutions for complex problems and more robust machine learning applications. The speed with which the quantum circuit can produce its randomized bit string is so great that there is no time to analyze and “cheat” the system.

“Quantum mechanical states do things that go beyond our day-to-day experience and so have the potential to provide capabilities and application that would otherwise be unattainable,” commented Joe Incandela, UC Santa Barbara’s vice chancellor for research. “The team has demonstrated the ability to reliably create and repeatedly sample complicated quantum states involving 53 entangled elements to carry out an exercise that would take millennia to do with a classical supercomputer. This is a major accomplishment. We are at the threshold of a new era of knowledge acquisition.”

Looking ahead

With an achievement like “quantum supremacy,” it’s tempting to think that the UC Santa Barbara/Google researchers will plant their flag and rest easy. But for Foxen, Chiaro, Martinis and the rest of the UCSB/Google AI Quantum group, this is just the beginning.

“It’s kind of a continuous improvement mindset,” Foxen said. “There are always projects in the works.” In the near term, further improvements to these “noisy” qubits may enable the simulation of interesting phenomena in quantum mechanics, such as thermalization, or the vast amount of possibility in the realms of materials and chemistry.

In the long term, however, the scientists are always looking to improve coherence times, or, at the other end, to detect and fix errors, which would take many additional qubits per qubit being checked. These efforts have been running parallel to the design and build of the quantum computer itself, and ensure the researchers have a lot of work before hitting their next milestone.

“It’s been an honor and a pleasure to be associated with this team,” Chiaro said. “It’s a great collection of strong technical contributors with great leadership and the whole team really synergizes well.”

Here’s a link to and a citation for the paper,

Quantum supremacy using a programmable superconducting processor by Frank Arute, Kunal Arya, Ryan Babbush, Dave Bacon, Joseph C. Bardin, Rami Barends, Rupak Biswas, Sergio Boixo, Fernando G. S. L. Brandao, David A. Buell, Brian Burkett, Yu Chen, Zijun Chen, Ben Chiaro, Roberto Collins, William Courtney, Andrew Dunsworth, Edward Farhi, Brooks Foxen, Austin Fowler, Craig Gidney, Marissa Giustina, Rob Graff, Keith Guerin, Steve Habegger, Matthew P. Harrigan, Michael J. Hartmann, Alan Ho, Markus Hoffmann, Trent Huang, Travis S. Humble, Sergei V. Isakov, Evan Jeffrey, Zhang Jiang, Dvir Kafri, Kostyantyn Kechedzhi, Julian Kelly, Paul V. Klimov, Sergey Knysh, Alexander Korotkov, Fedor Kostritsa, David Landhuis, Mike Lindmark, Erik Lucero, Dmitry Lyakh, Salvatore Mandrà, Jarrod R. McClean, Matthew McEwen, Anthony Megrant, Xiao Mi, Kristel Michielsen, Masoud Mohseni, Josh Mutus, Ofer Naaman, Matthew Neeley, Charles Neill, Murphy Yuezhen Niu, Eric Ostby, Andre Petukhov, John C. Platt, Chris Quintana, Eleanor G. Rieffel, Pedram Roushan, Nicholas C. Rubin, Daniel Sank, Kevin J. Satzinger, Vadim Smelyanskiy, Kevin J. Sung, Matthew D. Trevithick, Amit Vainsencher, Benjamin Villalonga, Theodore White, Z. Jamie Yao, Ping Yeh, Adam Zalcman, Hartmut Neven & John M. Martinis. Nature volume 574, pages505–510 (2019) DOI: https://doi.org/10.1038/s41586-019-1666-5 Issue Date 24 October 2019

This paper appears to be open access.

Quantum processor woven from light

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Weaving a quantum processor from light is a jaw-dropping event (as far as I’m concerned). An October 17, 2019 news item on phys.org makes the announcement,

An international team of scientists from Australia, Japan and the United States has produced a prototype of a large-scale quantum processor made of laser light.

Based on a design ten years in the making, the processor has built-in scalability that allows the number of quantum components—made out of light—to scale to extreme numbers. The research was published in Science today [October 18, 2019; Note: I cannot explain the discrepancy between the dates]].

Quantum computers promise fast solutions to hard problems, but to do this they require a large number of quantum components and must be relatively error free. Current quantum processors are still small and prone to errors. This new design provides an alternative solution, using light, to reach the scale required to eventually outperform classical computers on important problems.

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Caption: The entanglement structure of a large-scale quantum processor made of light. Credit: Shota Yokoyama 2019

An October 18, 2019 RMIT University (Australia) press release (also on EurekAlert but published October 17, 2019), which originated the news time, expands on the theme,

“While today’s quantum processors are impressive, it isn’t clear if the current designs can be scaled up to extremely large sizes,” notes Dr Nicolas Menicucci, Chief Investigator at the Centre for Quantum Computation and Communication Technology (CQC2T) at RMIT University in Melbourne, Australia.

“Our approach starts with extreme scalability – built in from the very beginning – because the processor, called a cluster state, is made out of light.”

Using light as a quantum processor

A cluster state is a large collection of entangled quantum components that performs quantum computations when measured in a particular way.

“To be useful for real-world problems, a cluster state must be both large enough and have the right entanglement structure. In the two decades since they were proposed, all previous demonstrations of cluster states have failed on one or both of these counts,” says Dr Menicucci. “Ours is the first ever to succeed at both.”

To make the cluster state, specially designed crystals convert ordinary laser light into a type of quantum light called squeezed light, which is then weaved into a cluster state by a network of mirrors, beamsplitters and optical fibres.

The team’s design allows for a relatively small experiment to generate an immense two-dimensional cluster state with scalability built in. Although the levels of squeezing – a measure of quality – are currently too low for solving practical problems, the design is compatible with approaches to achieve state-of-the-art squeezing levels.

The team says their achievement opens up new possibilities for quantum computing with light.

“In this work, for the first time in any system, we have made a large-scale cluster state whose structure enables universal quantum computation.” Says Dr Hidehiro Yonezawa, Chief Investigator, CQC2T at UNSW Canberra. “Our experiment demonstrates that this design is feasible – and scalable.”

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The experiment was an international effort, with the design developed through collaboration by Dr Menicucci at RMIT, Dr Rafael Alexander from the University of New Mexico and UNSW Canberra researchers Dr Hidehiro Yonezawa and Dr Shota Yokoyama. A team of experimentalists at the University of Tokyo, led by Professor Akira Furusawa, performed the ground-breaking experiment.

Here’s a link to and a citation for the paper,

Generation of time-domain-multiplexed two-dimensional cluster state by Warit Asavanant, Yu Shiozawa, Shota Yokoyama, Baramee Charoensombutamon, Hiroki Emura, Rafael N. Alexander, Shuntaro Takeda, Jun-ichi Yoshikawa, Nicolas C. Menicucci, Hidehiro Yonezawa, Akira Furusawa. Science 18 Oct 2019: Vol. 366, Issue 6463, pp. 373-376 DOI: 10.1126/science.aay2645

This paper is behind a paywall.

Bringing a technique from astronomy down to the nanoscale

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A January 2, 2020 Columbia University news release on EurekAlert (also on phys.org but published Jan. 3, 2020) describes research that takes the inter-galactic down to the quantum level,

Researchers at Columbia University and University of California, San Diego, have introduced a novel “multi-messenger” approach to quantum physics that signifies a technological leap in how scientists can explore quantum materials.

The findings appear in a recent article published in Nature Materials, led by A. S. McLeod, postdoctoral researcher, Columbia Nano Initiative, with co-authors Dmitri Basov and A. J. Millis at Columbia and R.A. Averitt at UC San Diego.

“We have brought a technique from the inter-galactic scale down to the realm of the ultra-small,” said Basov, Higgins Professor of Physics and Director of the Energy Frontier Research Center at Columbia. Equipped with multi-modal nanoscience tools we can now routinely go places no one thought would be possible as recently as five years ago.”

The work was inspired by “multi-messenger” astrophysics, which emerged during the last decade as a revolutionary technique for the study of distant phenomena like black hole mergers. Simultaneous measurements from instruments, including infrared, optical, X-ray and gravitational-wave telescopes can, taken together, deliver a physical picture greater than the sum of their individual parts.

The search is on for new materials that can supplement the current reliance on electronic semiconductors. Control over material properties using light can offer improved functionality, speed, flexibility and energy efficiency for next-generation computing platforms.

Experimental papers on quantum materials have typically reported results obtained by using only one type of spectroscopy. The researchers have shown the power of using a combination of measurement techniques to simultaneously examine electrical and optical properties.

The researchers performed their experiment by focusing laser light onto the sharp tip of a needle probe coated with magnetic material. When thin films of metal oxide are subject to a unique strain, ultra-fast light pulses can trigger the material to switch into an unexplored phase of nanometer-scale domains, and the change is reversible.

By scanning the probe over the surface of their thin film sample, the researchers were able to trigger the change locally and simultaneously manipulate and record the electrical, magnetic and optical properties of these light-triggered domains with nanometer-scale precision.

The study reveals how unanticipated properties can emerge in long-studied quantum materials at ultra-small scales when scientists tune them by strain.

“It is relatively common to study these nano-phase materials with scanning probes. But this is the first time an optical nano-probe has been combined with simultaneous magnetic nano-imaging, and all at the very low temperatures where quantum materials show their merits,” McLeod said. “Now, investigation of quantum materials by multi-modal nanoscience offers a means to close the loop on programs to engineer them.”

The excitement is palpable.

Caption: The discovery of multi-messenger nanoprobes allows scientists to simultaneously probe multiple properties of quantum materials at nanometer-scale spatial resolutions. Credit: Ella Maru Studio

Here’s a link to and a citation for the paper,

Multi-messenger nanoprobes of hidden magnetism in a strained manganite by A. S. McLeod, Jingdi Zhang, M. Q. Gu, F. Jin, G. Zhang, K. W. Post, X. G. Zhao, A. J. Millis, W. B. Wu, J. M. Rondinelli, R. D. Averitt & D. N. Basov. Nature Materials (2019) doi:10.1038/s41563-019-0533-y Published: 16 December 2019

This paper is behind a paywall.

Analyzing a buckyball’s (buckminsterfullerene) quantum structure

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The work was done jointly by the US National Institute of Standards and Technology (NIST) and JILA (Joint Institute for Laboratory Astrophysics), which is operated ‘jointly’ by NIST and the University of Colorado. On to buckyballs, a nickname for buckminsterfullerenes or C60.

From a January 28, 2019 news item on ScienceDaily,

JILA researchers have measured hundreds of individual quantum energy levels in the buckyball, a spherical cage of 60 carbon atoms. It’s the largest molecule that has ever been analyzed at this level of experimental detail in the history of quantum mechanics. Fully understanding and controlling this molecule’s quantum details could lead to new scientific fields and applications, such as an entire quantum computer contained in a single buckyball.

Caption: JILA researchers used frequency combs, or “rulers of light,” to observe individual quantum energy transitions in buckyballs. Credit: Steven Burrows/JILA

There are two types of spherical objects in the image: the smooth blue ones, which are not buckyballs, and the ones with ridged spheres, which are.

A January 28, 2019 NIST news release (also on EurekAlert), which originated the news item, describes the buckyball molecule and the research in more detail,

The buckyball, formally known as buckminsterfullerene, is extremely complex. Due to its enormous 60-atom size, the overall molecule has a staggeringly high number of ways to vibrate–at least 100,000,000,000,000,000,000,000,000 vibrational quantum states when the molecule is warm. That’s in addition to the many different energy states for the buckyball’s rotation and other properties.

As described in the January 4 [2019] issue of Science, the JILA team used an updated version of their frequency comb spectroscopy and cryogenic buffer gas cooling system to observe isolated, individual energy transitions among rotational and vibrational states in cold, gaseous buckyballs. This is the first time anyone has been able to prepare buckyballs in this form to analyze its rotations and vibrations at the quantum level.

JILA is jointly operated by the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder.

Buckyballs, first discovered in 1984, have created great scientific excitement. But high-resolution spectroscopy, which can reveal the details of the molecule’s rotational and vibrational properties, didn’t work at ordinary room temperatures because the signals were too congested, NIST/JILA Fellow Jun Ye said. Low temperatures (about -138 degrees Celsius, which is -216 degrees Fahrenheit) enabled researchers to concentrate the molecules into a single rotational-vibrational quantum state at the lowest energy level and probe them with high-resolution spectroscopy.

The buckyball is the most symmetric molecule known, with a soccer-ball-like shape known as a modified icosahedron. It is small enough to be fully understood with basic quantum mechanics principles. Yet it is large enough to reveal insights into the extreme quantum complexity that emerges in huge systems.

As an example of practical applications, buckyballs could act as a pristine network of 60 atoms. The core of each atom possesses an identical property known as “nuclear spin,” which enables it to interact magnetically with its environment. Therefore, each spin could act as a magnetically controlled quantum bit or “qubit” in a quantum computer.

“If we had a buckyball made of pure isotopic carbon-13, each atom would have a nuclear spin of 1/2, and each buckyball could serve as a 60-qubit quantum computer,” Ye said. “Of course, we don’t have such capabilities yet; we would need to first capture these buckyballs in traps.”

A key part of the new quantum revolution, a quantum computer using qubits made of atoms or other materials could potentially solve important problems that are intractable using today’s machines. NIST has a major stake in quantum science

“There are also a lot of astrophysics connections,” Ye continued. “There are abundant buckyball signals coming from remote carbon stars,” so the new data will enable scientists to better understand the universe.

After they measured the quantum energy levels, the JILA researchers collected statistics on buckyballs’ nuclear spin values. They confirmed that all 60 atoms were indistinguishable, or virtually identical. Precise measurements of the buckyball’s transition energies between individual quantum states revealed its atoms interacted strongly with one another, providing insights into the complexities of its molecular structure and the forces between atoms.

For the experiments, an oven converted a solid sample of material into gaseous buckyballs. These hot molecules flowed into a cell (container) anchored to a cryogenic cold apparatus, such that the molecules were cooled by collisions with cold argon gas atoms. Then laser light at precise frequencies was aimed at the cold gas molecules, and researchers measured how much light was absorbed. The observed structure in the infrared spectrum encoded details of the quantum-mechanical energy-level structure.

The laser light was produced by an optical frequency comb, or “ruler of light,” and aimed into an optical cavity surrounding the cold cell to enhance the absorption signals. The comb contained about 1000 “teeth” at optical frequencies spanning the full band of buckyball vibrations. The comb light was generated from a single fiber laser.

Here’s a link to and a citation for the paper,

Rovibrational quantum state resolution of the C60 fullerene by P. Bryan Changala, Marissa L. Weichman, Kevin F. Lee, Martin E. Fermann, Jun Ye1. Science 04 Jan 2019: Vol. 363, Issue 6422, pp. 49-54 DOI: 10.1126/science.aav2616

This paper appears to be open access.