Tag Archives: encryption

Novel visible light communication encryption technology using chiral nanoparticles

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One of the most intriguing (yes, it’s a pun) encryption stories (for me) is centuries old and concerns Mary Queen of Scots, from a February 10, 2023 article by Meilan Solly for Smithsonian Magazine, Note: Links have been removed,

Over the course of her 19 years in captivity, Mary, Queen of Scots, wrote thousands of letters to ambassadors, government officials, fellow monarchs and conspirators alike. Most of these missives had the same underlying goal: securing the deposed Scottish queen’s freedom. After losing her throne in 1567, Mary had fled to England, hoping to find refuge at her cousin Elizabeth I’s court. (Mary’s paternal grandmother, Margaret Tudor, was the sister of Elizabeth’s father, Henry VIII.) Instead, the English queen imprisoned Mary, keeping her under house arrest for nearly two decades before ordering her execution in 1587.

Mary’s letters have long fascinated scholars and the public, providing a glimpse into her relentless efforts to secure her release. But the former queen’s correspondence often raises more questions than it answers, in part because Mary took extensive steps to hide her messages from the prying eyes of Elizabeth’s spies. In addition to folding the pages with a technique known as letterlocking, she employed ciphers and codes of varying complexity.

More than 400 years after Mary’s death, a chance discovery by a trio of code breakers is offering new insights into the queen’s final years. As the researchers write in the journal Cryptologia, they originally decided to examine a cache of coded notes housed at the National Library of France as part of a broader push to “locate, digitize, transcribe, decipher and analyze” historic ciphers. Those pages turned out to be 57 of Mary’s encrypted letters, the majority of which were sent to Michel de Castelnau, the French ambassador to England, between 1578 and 1584. All but seven were previously thought to be lost.

Interspersed with a collection of early 16th-century Italian papers, the documents were written in mysterious symbols that offered no clues “as to their sender, recipients or date,” lead author George Lasry, a computer scientist and cryptographer based in Israel, tells Smithsonian magazine. It was only when the scholars spotted the word “Walsingham”—the last name of Elizabeth’s spymaster, Francis Walsingham—that they realized the letters’ significance.

“This was the ‘bingo moment,’” Lasry says. “We were very excited.”

Before getting too excited, the trio set out to confirm whether the letters were already known to historians. While they found copies of a few in British archives, “50 or so are new to historians—and a real gold mine for them,” says Lasry. In total, the letters contain 50,000 words of deciphered material.

…

Fascinating, non?

An October 10, 2024 news item on Nanowerk sheds light (more wordplay) on a contemporary approach to encryption,

Seoul National University(SNU) College of Engineering announced that a joint research team led by Professor Ki Tae Nam from the Department of Materials Science and Engineering at SNU and Professor Junil Choi from the Korea Advanced Institute of Science and Technology (KAIST) has developed a novel visible light communication encryption technology with high security using chiral nanoparticles.

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A September 30, 2024 Seoul National University (SNU) press release (also on EurekAlert but published on October 10, 2024), which originated the news item, describes the research in more detail,

Just as a lighthouse provides a guiding beam in the vast darkness of the sea, light-based information transmission has been a crucial means of communication throughout human history. Recently, next-generation communication technology based on visible light, which possesses high frequencies and linearity, has gained attention. It offers advantages such as integration with lighting systems and is free from the electromagnetic interference associated with conventional communication networks. With high security and fast transmission speeds, visible light communication is particularly suitable for local communication systems, especially in military operations involving vehicles, drones, and personnel.

In addition to intensity and wavelength (color), light can carry a vast amount of information through polarization. For instance, 3D movies use polarized filters to deliver two different polarized images to the viewer’s eyes, creating a sense of depth. Recently, efforts have been made to improve the security and performance of visible light communication, including the incorporation of technologies related to polarization, such as quantum information communication based on the superposition of polarization.

The SNU-KAIST joint research team focused on how light polarization can be significantly modulated through interaction with nanomaterials. In this study, they developed an innovative visible light communication encryption technology based on new materials. The core of this technology lies in chiral nanomaterials, which exhibit a symmetric structure when viewed in a mirror but do not overlap. These materials can significantly adjust the tilt of the polarization axis or its rotational properties. Having previously published two papers in 2018 and 2022 in the prestigious journal Nature on “the synthesis and optical device application of chiral nanoparticles with world-class polarization control performance,” the research team has now introduced a visible light communication encryption technology that cannot be replicated or intercepted without detailed information about the nanoparticles.

The chiral nanoparticles used in this technology are created by twisting their crystal structure using biomolecules like proteins and DNA, which possess natural chirality. The optical properties of these nanoparticles cannot be replicated without complete sequence information of the biomolecules used in their synthesis. Therefore, chiral nanoparticles function like fingerprints or unclonable keys in visible light communication, allowing only the receiver with the actual nanoparticles to correctly decode the information. This encryption technology is expected to have significant utility in secure point-to-point communication systems, such as those used in military operations involving drones.

Furthermore, the research team developed a spatiotemporal polarization control device capable of transmitting encrypted polarization information. By combining quantum nanorods, which efficiently emit polarized light, with nanowire materials that provide rotational properties to the light, they used 3D printing to fabricate a polarization control device with hundreds of micrometers of spatial resolution and nanoseconds of temporal resolution, allowing all polarization states to be represented without restriction. The transmitting unit can encrypt and transmit polarization information in a form suited to the polarization control properties of the nanoparticles using this device. This technology is expected to be the foundation for mass production of devices that can control spatiotemporal polarization without being constrained by form factor.

Professor Ki Tae Nam from SNU’s Department of Materials Science and Engineering said, “This research, which actively combines new material technologies with communication technologies, played a crucial role in developing the world’s first and only visible light communication encryption technology. We expect this technology to not only contribute to national defense but also be commercialized rapidly in industrial fields like display technology.” Professor Junil Choi from KAIST’s School of Electrical Engineering added, “This outstanding research result was achieved through joint efforts between material science and electrical engineering experts. In the future, we aim to further develop visible light communication technology based on nanoparticles to create communication systems that are fundamentally impossible to eavesdrop on.” Co-first author Jeong Hyun Han also stated, “We anticipate that this encryption system will act as a platform with great scalability and impact in the field of optical information transmission based on polarization.”

This research was supported by the Future Defense Technology Development Program of the Agency for Defense Development, the Basic Research Laboratory Program of the National Research Foundation of Korea, and private support from LG Display. The research outcome, which has been recognized for its significance, was published in the prestigious multidisciplinary journal Nature Communications on September 27 [2024].

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

Spatiotemporally modulated full-polarized light emission for multiplexed optical encryption by Jiawei Lv, Jeong Hyun Han, Geonho Han, Seongmin An, Seung Ju Kim, Ryeong Myeong Kim, Jung‐El Ryu, Rena Oh, Hyuckjin Choi, In Han Ha, Yoon Ho Lee, Minje Kim, Gyeong-Su Park, Ho Won Jang, Junsang Doh, Junil Choi & Ki Tae Nam. Nature Communications volume 15, Article number: 8257 (2024) DOI: https://doi.org/10.1038/s41467-024-52358-7 Published: 27 September 2024

This paper is open access.

A biochemical means of protecting passwords and anti-counterfeiting solution for art and other precious goods

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I guess you could say my passwords are as precious to me as a piece.of art is to some people.

DNA can be used to confirm the authenticity of valuable art prints. (AI-​generated image: ETH Zurich)

An April 8, 2024 ETH Zurich press release (also on EurekAlert) by Fabio Bergamin features an approach that could make passwords secure from quantum computers, Note: A link has been removed,

Security experts fear Q-​Day, the day when quantum computers become so powerful that they can crack today’s passwords. Some experts estimate that this day will come within the next ten years. Password checks are based on cryptographic one-​way functions, which calculate an output value from an input value. This makes it possible to check the validity of a password without transmitting the password itself: the one-​way function converts the password into an output value that can then be used to check its validity in, say, online banking. What makes one-​way functions special is that it’s impossible to use their output value to deduce the input value – in other words, the password. At least not with today’s resources. However, future quantum computers could make this kind of inverse calculation easier.

Researchers at ETH Zurich have now presented a cryptographic one-​way function that works differently from today’s and will also be secure in the future. Rather than processing the data using arithmetic operations, it is stored as a sequence of nucleotides – the chemical building blocks of DNA.

Based on true randomness

“Our system is based on true randomness. The input and output values are physically linked, and it’s only possible to get from the input value to the output value, not the other way round,” explains Robert Grass, a professor in the Department of Chemistry and Applied Biosciences. “Since it’s a physical system and not a digital one, it can’t be decoded by an algorithm, not even by one that runs on a quantum computer,” adds Anne Lüscher, a doctoral student in Grass’s group. She is the lead author of the paper, which was published in the journal Nature Communications.

The researchers’ new system can serve as a counterfeit-​proof way of certifying the authenticity of valuable objects such as works of art. The technology could also be used to trace raw materials and industrial products.

How it works

The new biochemical one-​way function is based on a pool of one hundred million different DNA molecules. Each of the molecules contains two segments featuring a random sequence of nucleotides: one segment for the input value and one for the output value. There are several hundred identical copies of each of these DNA molecules in the pool, and the pool can also be divided into several pools; these are identical because they contain the same random DNA molecules. The pools can be located in different places, or they can be built into objects.

Anyone in possession of this DNA pool holds the security system’s lock. The polymerase chain reaction (PCR) can be used to test a key, or input value, which takes the form of a short sequence of nucleotides. During the PCR, this key searches the pool of hundreds of millions of DNA molecules for the molecule with the matching input value, and the PCR then amplifies the output value located on the same molecule. DNA sequencing is used to make the output value readable.

At first glance, the principle seems complicated. “However, producing DNA molecules with built-​in randomness is cheap and easy,” Grass says. The production costs for a DNA pool that can be divided up in this way are less than 1 Swiss franc. Using DNA sequencing to read out the output value is more time-​consuming and expensive, but many biology laboratories already possess the necessary equipment.

Securing valuable goods and supply chains

ETH Zurich has applied for a patent on this new technology. The researchers now want to optimise and refine it to bring it to market. Because using the method calls for specialised laboratory infrastructure, the scientists think the most likely application for this form of password verification is currently for highly sensitive goods or for access to buildings with restricted access. This technology won’t be an option for the broader public to check passwords until DNA sequencing in particular becomes easier.

A little more thought has already gone into the idea of using the technology for the forgery-​proof certification of works of art. For instance, if there are ten copies of a picture, the artist can mark them all with the DNA pool – perhaps by mixing the DNA into the paint, spraying it onto the picture or applying it to a specific spot.

If several owners later wish to have the authenticity of these artworks confirmed, they can get together, agree on a key (i.e. an input value) and carry out the DNA test. All the copies for which the test produces the same output value will have been proven genuine. The new technology could also be used to link crypto-​assets such as NFTs, which exist only in the digital world, to an object and thus to the physical world.

Furthermore, it would support counterfeit-​proof tracking along supply chains of industrial goods or raw materials. “The aviation industry, for example, has to be able to provide complete proof that it uses only original components. Our technology can guarantee traceability,” Grass says. In addition, the method could be used to label the authenticity of original medicines or cosmetics.

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

Chemical unclonable functions based on operable random DNA pools by Anne M. Luescher, Andreas L. Gimpel, Wendelin J. Stark, Reinhard Heckel & Robert N. Grass. Nature Communications volume 15, Article number: 2955 (2024) DOI: https://doi.org/10.1038/s41467-024-47187-7 Published: 05 April 2024

This paper is open access.

Concerns about Zoom? Call for expressions of interest in “Zoom Obscura,” creative interventions for a data ethics of video conferencing

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Have you wondered about Zoom video conferencing and all that data being made available? Perhaps questioned ethical issues in addition to those associated with data security? Is so and you’d like to come up with a creative intervention that delves beyond encryption issues, there’s Zoom Obscura (on the creativeinformatics.org website),

CI [Creative Informatics] researchers Pip Thornton, Chris Elsden and Chris Speed were recently awarded funding from the Human Data Interaction Network (HDI +) Ethics & Data competition. Collaborating with researchers from Durham [Durham University] and KCL [Kings College London], the Zoom Obscura project aims to investigate creative interventions for a data ethics of video conferencing beyond encryption.

The COVID-19 pandemic has gifted video conferencing companies, such as Zoom, with a vast amount of economically valuable and sensitive data such as our facial and voice biometrics, backgrounds and chat scripts. Before the pandemic, this ‘new normal’ would be subject to scrutiny, scepticism and critique. Yet, the urgent need for remote working and socialising left us with little choice but to engage with these potentially exploitative platforms.

While much of the narrative around data security revolves around technological ‘solutions’ such as encryption, we think there are other – more creative – ways to push back against the systems of digital capitalism that continue to encroach on our everyday lives.

As part of this HDI-funded project, we seek artists, hackers and creative technologists who are interested in experimenting with creative methods to join us in a series of online workshops that will explore how to restore some control and agency in how we can be seen and heard in these newly ubiquitous online spaces. Through three half-day workshops held remotely, we will bring artists and technicians together to ideate, prototype, and exhibit various interventions into the rapidly normalising culture of video-calling in ways that do not compromise our privacy and limit the sharing of our data. We invite interventions that begin at any stage of the video-calling process – from analogue obfuscation, to software manipulation or camera trickery.

Selected artists/collectives will receive a £1000 commission to take part and contribute in three workshops, in order to design and produce one or more, individual or collaborative, creative interventions developed from the workshops. These will include both technical support from a creative technologist as well as a curator for dissemination both online and in Edinburgh and London.

If you are an artist / technologist interested in disrupting/subverting the pandemic-inspired digital status quo, please send expressions of interest of no more than 500 words to pip.thornton@ed.ac.uk , andrew.dwyer@bristol.ac.uk, celsden@ed.ac.uk and michael.duggan@kcl.ac.uk by 8th October 2020. We don’t expect fully formed projects (these will come in the workshop sessions), but please indicate any broad ideas and thoughts you have, and highlight how your past and present practice might be a good fit for the project and its aims.

The Zoom Obscura project is in collaboration with Tinderbox Lab in Edinburgh and Hannah Redler-Hawes (independent curator and codirector of the Data as Culture art programme at the Open Data Institute in London). Outputs from the project will be hosted and exhibited via the Data as Culture archive site and at a Creative Informatics event at the University of Edinburgh.

Are folks outside the UK eligible?

I asked Dr. Pip Thornton about eligibility and she kindly noted this in her Sept. 25, 2020 tweet (reply copied from my Twitter feed),

Open to all, but workshop timings may be more amenable to UK working hours. Having said that, we won’t know what the critical mass is until we review all the applications, so please do apply if you’re interested!

Who are the members of the Zoom Obscura project team?

From the Zoom Obscura webpage (on the creativeinformatics.org website),

Dr. Pip Thornton is a post-doctoral research associate in Creative Informatics at the University of Edinburgh, having recently gained her PhD in Geopolitics and Cybersecurity from Royal Holloway, University of London. Her thesis, Language in the Age of Algorithmic Reproduction: A Critique of Linguistic Capitalism, included theoretical, political and artistic critiques of Google’s search and advertising platforms. She has presented in a variety of venues including the Science Museum, the Alan Turing Institute and transmediale. Her work has featured in WIRED UK and New Scientist, and a collection from her {poem}.py intervention has been displayed at Open Data Institute in London. Her Edinburgh Futures Institute (EFI) funded installation Newspeak 2019, shown at the Edinburgh Festival Fringe (2019), was recently awarded an honourable mention in the Surveillance Studies Network biennial art competition (2020) and is shortlisted for the 2020 Lumen Prize for art and technology in the AI category.

Dr. Andrew Dwyer is a research associate  in the University of Bristol’s Cyber Security Group. Andrew gained a DPhil in Cyber Security at the University of Oxford, where he studied and questioned the role of malware – commonly known as computational viruses and worms –  through its analysis, detection, and translation into international politics and its intersection with multiple ecologies. In his doctoral thesis – Malware Ecologies: A Politics of Cybersecurity – he argued for a re-evaluation of the role of computational actors in the production and negotiation of security, and what this means for human-centred notions of weapons and warfare. Previously, Andrew has been a visiting fellow at the German ‘Dynamics of Security’ collaborative research centre based between Philipps-Universität Marburg, Justus-Liebig-Universität Gießen and the Herder Institute, Marburg and is a Research Affiliate at the Centre for Technology and Global Affairs at the University of Oxford. He will soon be starting a 3-year Addison Wheeler research fellowship in the Department of Geography at the Durham University

Dr Chris Elsden is a research associate in Design Informatics at the University of Edinburgh. Chris is primarily working on the AHRC Creative Informatics project., with specific interests in FinTech and livestreaming within the Creative Industries. He is an HCI researcher, with a background in sociology, and expertise in the human experience of a data-driven life. Using and developing innovative design research methods, his work undertakes diverse, qualitative and often speculative engagements with participants to investigate emerging relationships with technology – particularly data-driven tools and financialn technologies. Chris gained his PhD in Computer Science at Open Lab, Newcastle University in 2018, and in 2019 was a recipient of a SIGCHI Outstanding Dissertation Award.

Dr Mike Duggan is a Teaching Fellow in Digital Cultures in the Department of Digital Humanities at Kings College London. He was awarded a PhD in Cultural Geography from Royal Holloway University of London in 2017, which examined everyday digital mapping practices. This project was co-funded by the Ordnance Survey and the EPSRC. He is a member of the Living Maps network, where he is an editor for the ‘navigations’ section and previously curated the seminar series. Mike’s research is broadly interested in the digital and cultural geographies that emerge from the intersections between everyday life and digital technology.

Professor Chris Speed is Chair of Design Informatics at the University of Edinburgh where his research focuses upon the Network Society, Digital Art and Technology, and The Internet of Things. Chris has sustained a critical enquiry into how network technology can engage with the fields of art, design and social experience through a variety of international digital art exhibitions, funded research projects, books journals and conferences. At present Chris is working on funded projects that engage with the social opportunities of crypto-currencies, an internet of toilet roll holders, and a persistent argument that chickens are actually robots.  Chris is co-editor of the journal Ubiquity and co-directs the Design Informatics Research Centre that is home to a combination of researchers working across the fields of interaction design, temporal design, anthropology, software engineering and digital architecture, as well as the PhD, MA/MFA and MSc and Advanced MSc programmes.

David Chatting is a designer and technologist who works in software and hardware to explore the impact of emerging technologies in everyday lives. He is currently a PhD student in the Department of Design at Goldsmiths – University of London, a Visiting Researcher at Newcastle University’s Open Lab and has his own design practice. Previously he was a Senior Researcher at BTs Broadband Applications Research Centre. David has a Masters degree in Design Interactions from the Royal College of Art (2012) and a Bachelors degree in Computer Science from the University of Birmingham (2000). He has published papers and filed patents in the fields of HCI, psychology, tangible interfaces, computer vision and computer graphics.

Hannah Redler Hawes (Data as Culture) is an independent curator and codirector of the Data as Culture art programme at the Open Data Institute in London. Hannah specialises in emerging artistic practice within the fields of art and science and technology, with an interest in participatory process. She has previously developed projects for museums, galleries, corporate contexts, digital space and the public realm including the  Institute of Physics, Tate Modern, The Lowry, Natural History Museum, FACT Liverpool, the Digital Catapult and Science Gallery London, and has provided specialist consultancy services to the Wellcome Collection, Discover South Kensington and the Horniman Museum. Hannah enjoys projects that redraw boundaries between different disciplines. Current research is around addiction, open data, networked culture and new forms of programming beyond the gallery.

Tinderbox Collective : From grass-roots youth work to award-winning music productions, Tinderbox is building a vibrant and eclectic community of young musicians and artists in Scotland. We have a number of programmes that cross over with each other and come together wherever possible.  They are open to children and young people aged 10 – 25, from complete beginners to young professionals and all levels in between. Tinderbox Lab is our digital arts programme and shared studio maker-space in Edinburgh that brings together artists across disciplines with an interest in digital media and interactive technologies. It is a new programme that started development in 2019, leading to projects and events such as Room to Play, a 10-week course for emerging artists led by Yann Seznec; various guest artist talks & workshops; digital arts exhibitions at the V&A Dundee & Edinburgh Festival of Sound; digital/electronics workshops design/development for children & young people; and research included as part of Electronic Visualisation and the Arts (EVA) London 2019 conference.

Jack Nissan (Tinderbox) is the founder and director of the Tinderbox Collective. In 2012/13, Jack took part in a fellowship programmed called International Creative Entrepreneurs and spent several months working with community activists and social enterprises in China, primarily with families and communities on the outskirts of Beijing with an organisation called Hua Dan. Following this, he set up a number of international exchanges and cross-cultural productions that formed the basis for Tinderbox’s Journey of a Thousand Wings programme, a project bringing together artists and community projects from different countries. He is also a co-director and founding member of Hidden Door, a volunteer-run multi-arts festival, and has won a number of awards for his work across creative and social enterprise sectors. He has been invited to take part in several steering committees and advisory roles, including for Creative Scotland’s new cross-cutting theme on Creative Learning and Artworks Scotland’s peer-networks for artists working in participatory settings. Previously, Jack worked as a researcher in psychology and ageing for the multidisciplinary MRC Centre for Cognitive Ageing and Cognitive Epidemiology, specialising in areas of neuropsychology and memory.

Luci Holland (Tinderbox) is a Scottish (Edinburgh-based) composer, sound artist and radio presenter who composes and produces music and audiovisual art for film, games and concert. As a games music composer Luci wrote the original dynamic/responsive music for Blazing Griffin‘s 2018 release Murderous Pursuits, and has composed and arranged for numerous video game music collaborations, such as orchestrating and producing an arrangement of Jessica Curry‘s Disappearing with label Materia Collective’s bespoke cover album Pattern: An Homage to Everybody’s Gone to the Rapture. Currently she has also been composing custom game music tracks for Skyrim mod Lordbound and a variety of other film and game music projects. Luci also builds and designs interactive sonic art installations for festivals and venues (Refraction (Cryptic), CITADEL (Hidden Door)); and in 2019 Luci joined new classical music station Scala Radio to present The Console, a weekly one-hour show dedicated to celebrating great music in games. Luci also works as a musical director and composer with the youth music charity Tinderbox Project on their Orchestra & Digital Arts programmes; classical music organisation Absolute Classics; and occasionally coordinates musical experiments and productions with her music-for-media band Mantra Sound.

Good luck to all who submit an expression of interest and good luck to Dr. Thornton (I see from her bio that she’s been shortlisted for the 2020 Lumen Prize).

Cryptology exhibit and special breakfast celebrating Canadian astronaut David Saint-Jacques’ Dec. 3, 2018 launch in Ontario (Canada)

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I wish I was near either Ottawa or Kingston in December as there are a couple of very interesting events, assuming you have an interest in cryptology and/or space travel.

Cipher/Decipher

This show has been on tour in Ontario and, until Dec. 2, 2018, it will be at the Canada Science and Technology Museum before moving to Kingston (from the Canada Science and Technology Museum’s exhibitions page),

Cipher | Decipher

Pssst…want to know a secret?

One way to safely share secret information is through encryption — which means converting your message into something only the intended recipient can understand. For as long as we’ve had secret information, individuals and organizations have encrypted and analyzed encrypted communications. One way people encrypt their secrets is through ciphers that replace the original message with other letters, numbers, words, or symbols. From schoolyard gossip to military plans, ciphers keep secrets out of the wrong hands.

Cipher | Decipher is an interactive, new exhibition exploring the past and present of communications cryptology — what it is, how it works, and how it affects our lives. See an authentic Enigma cipher machine, or try your hand at logic puzzles and games to see if you have what it takes to work in the field of cryptology!

Developed by the Canada Science and Technology Museum, in partnership with the Communications Security Establishment, this 750 sq. ft. travelling exhibition is already on the move!

Mark your calendar to see Cipher | Decipher at the following locations:

  • Library and Archives Canada: October 5 to October 31, 2018
  • Canada Science and Technology Museum: November 6 to December 2, 2018
  • Military Communications and Electronics Museum, Kingston: December 7, 2018 to March 31, 2019

Blast-off!

This information came in a November 27, 2018 special announcement (received via email) from Ingenium (formerly Canada Science and Technology Museums Corporation and not to be confused with the Canada Science and Technology Museum),

Join the Canada Aviation and Space Museum for a special breakfast at the museum, as we witness the historic launch of Canadian astronaut David Saint-Jacques!

Start your day with a breakfast and a big cup of “rocket fuel” (a.k.a. coffee) as we watch the launch of this important space mission.

You’ll hear from Jesse Rogerson, the museum’s Science Advisor, and Iain Christie,

Executive Vice President of the Aerospace Industries Association of Canada about the intricacies of space travel. Canadian astronauts Bob Thirsk and Jenni Sidey-Gibbons will also join the conversation via livestream!

Take a selfie with our cut-out image of David Saint-Jacques, while the kids work on fun space-themed crafts. David Saint-Jacques themed merchandise will be 10% off during the event. Each purchase of a breakfast ticket/group of tickets will receive one FREE family pass, to visit the museum in 2019.

December 3, 2018
6 a.m. – 8:30 a.m.
Tickets: $16 (+ taxes)
Parking fees are additional.

Buy Tickets!

3… 2… 1… liftoff!

Enjoy!

Doped carbon nanotubes and a new path to quantum encryption

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An April 12, 2016 news item on ScienceDaily describes a use for  carbon nanotubes in the field of quantum encryption,

Critical information, ranging from credit card numbers to national security data, is sent in streams of light, or laser pulses. However, the data transmitted in this manner can be stolen by splitting out a few photons (packets of light) from the laser pulse. Such eavesdropping could be prevented by encoding the data into single photons. But that requires generating single photons. Researchers demonstrated a new material, made from tiny carbon tubes, that emits the desired photons at room temperature.

A March 31, 2016 US Department of Energy news release, which originated the news item, explains the concept in more detail,

Digital eavesdropping could be prevented by encoding bits of information in the properties, or quantum mechanical states, of single photons. Single photons emitted by carbon nanotubes altered, or doped with oxygen, are especially attractive for realizing this quantum information technology.

Summary

Single photon generation requires an isolated, quantum mechanical, two-level system that can emit only one photon in one excitation-emission cycle. While artificial nanoscale materials (such as quantum dots and vacancy centers in diamonds) have been explored for single photon generation, none have emerged as the ideal candidate that meets all of the technological requirements. These requirements include the ability to generate single photons in the 1.3 to 1.5 µm fiber optic telecommunication wavelength range at room temperature. Earlier studies revealed that carbon nanotubes were not suited for use in quantum communications because the tubes required extremely low temperatures and had strong photoluminescence fluctuations. In contrast to these earlier findings, researchers led by Han Htoon and Stephen Doorn of the Center for Integrated Nanotechnologies showed that oxygen doping of carbon nanotubes can lead to fluctuation-free photoluminescence emission in the telecommunication wavelength range. Experiments measuring the time-distribution of two successive photon emission events also unambiguously demonstrated single photon emission at room temperature. Furthermore, because oxygen doping is achieved through a simple deposition of a silicon dioxide layer, these doped carbon nanotubes are fully compatible with silicon microfabrication technology and can be fabricated into electrically driven single photon sources. In addition, the silicon dioxide layer encapsulating the nanotubes allows for their easy integration into electronic and photonic integrated circuits. Beyond the implementation of this new method into quantum communication technologies, nanotube-based single photon sources could enable other transformative quantum technologies, including ultra-sensitive absorption measurements, sub-diffraction imaging, and linear quantum computing.

The researchers have provided an illustration of doped carbon nanotubes,

The deposition of a silicon dioxide layer (yellow layer) on a carbon nanotube (gray spheres) introduces solitary oxygen dopants (red spheres). A single photon (red and white star) is emitted when a dopant is excited by a laser pulse (green arrow). Image courtesy of the Center for Integrated Nanotechnologies

The deposition of a silicon dioxide layer (yellow layer) on a carbon nanotube (gray spheres) introduces solitary oxygen dopants (red spheres). A single photon (red and white star) is emitted when a dopant is excited by a laser pulse (green arrow). Image courtesy of the Center for Integrated Nanotechnologies

Here’s a link to and a citation for the paper, which was published a surprisingly long time ago,

Room-temperature single-photon generation from solitary dopants of carbon nanotubes by Xuedan Ma, Nicolai F. Hartmann, Jon K. S. Baldwin, Stephen K. Doorn, & Han Htoon.  Nature Nanotechnology 10, 671–675 (2015)  doi:10.1038/nnano.2015.136 Published online 13 July 2015

This paper is behind a paywall.