Tag Archives: Institute for Quantum Computing (IQC)

University of Waterloo researchers get one step closer to secure quantum communication on a global scale

A March 25, 2024 news item on phys.org announcds Canadian research into quantum communication, Note: Links have been removed,

Researchers at the University of Waterloo’s Institute for Quantum Computing (IQC) have brought together two Nobel prize-winning research concepts to advance the field of quantum communication.

Scientists can now efficiently produce nearly perfect entangled photon pairs from quantum dot sources. The research, “Oscillating photonic Bell state from a semiconductor quantum dot for quantum key distribution,” was published in Communications Physics

A March 25, 2024 University of Waterloo news release (also on EurekAlert), which originated the news item, delves further into the topic of quantum physics and communication,

Entangled photons are particles of light that remain connected, even across large distances, and the 2022 Nobel Prize in Physics recognized experiments on this topic. Combining entanglement with quantum dots, a technology recognized with the Nobel Prize in Chemistry in 2023, the IQC research team aimed to optimize the process for creating entangled photons, which have a wide variety of applications, including secure communications.

“The combination of a high degree of entanglement and high efficiency is needed for exciting applications such as quantum key distribution or quantum repeaters, which are envisioned to extend the distance of secure quantum communication to a global scale or link remote quantum computers,” said Dr. Michael Reimer, professor at IQC and Waterloo’s Department of Electrical and Computer Engineering. “Previous experiments only measured either near-perfect entanglement or high efficiency, but we’re the first to achieve both requirements with a quantum dot.”

By embedding semiconductor quantum dots into a nanowire, the researchers created a source that creates near-perfect entangled photons 65 times more efficiently than previous work. This new source, developed in collaboration with the National Research Council of Canada in Ottawa, can be excited with lasers to generate entangled pairs on command. The researchers then used high-resolution single photon detectors provided by Single Quantum in The Netherlands to boost the degree of entanglement.

“Historically, quantum dot systems were plagued with a problem called fine structure splitting, which causes an entangled state to oscillate over time. This meant that measurements taken with a slow detection system would prevent the entanglement from being measured,” said Matteo Pennacchietti, a PhD student at IQC and Waterloo’s Department of Electrical and Computer Engineering. “We overcame this by combining our quantum dots with a very fast and precise detection system. We can basically take a timestamp of what the entangled state looks like at each point during the oscillations, and that’s where we have the perfect entanglement.”

To showcase future communications applications, Reimer and Pennacchietti worked with Dr. Norbert Lütkenhaus and Dr. Thomas Jennewein, both IQC faculty members and professors in Waterloo’s Department of Physics and Astronomy, and their teams. Using their new quantum dot entanglement source, the researchers simulated a secure communications method known as quantum key distribution, proving that the quantum dot source holds significant promise in the future of secure quantum communications.

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

Oscillating photonic Bell state from a semiconductor quantum dot for quantum key distribution by Matteo Pennacchietti, Brady Cunard, Shlok Nahar, Mohd Zeeshan, Sayan Gangopadhyay, Philip J. Poole, Dan Dalacu, Andreas Fognini, Klaus D. Jöns, Val Zwiller, Thomas Jennewein, Norbert Lütkenhaus & Michael E. Reimer. Communications Physics volume 7, Article number: 62 (2024)
DOI: https://doi.org/10.1038/s42005-024-01547-3 Published: 24 February 2024

This paper is open access.

Smallest national flag record achieved to celebrate Canada’s 150th birthday

Courtesy University of Waterloo

Courtesy University of Waterloo

This is a partly nanoscale Canadian flag. For those who can’t read the text on the image, it says ‘Cursor Height = 501.7 nanometers [and] Cursor Width = 1.178 micrometers’.

A Sept. 19, 2016 news item on phys.org announces the latest ‘small’ flag,

The Institute for Quantum Computing at the University of Waterloo set a world record for creating a Canadian flag measuring about one one-hundredth the width of a human hair.

Guinness World Records granted the inaugural award for smallest national flag to the Institute for Quantum Computing (IQC) at Waterloo for the flag measuring 1.178 micrometres in length. It is invisible without the aid of an electron microscope.

A Sept. 19, 2016 University of Waterloo (Ontario, Canada) news release, which originated the news item, provides more detail about how the flag was fabricated (Note: A link has been removed),

Nathan Nelson-Fitzpatrick, nanofabrication process engineer at IQC, led the creation of the flag with assistance from Natalie Prislinger Pinchin, a Waterloo co-op student from the Faculty of Engineering. They created it on a silicon wafer bearing the official logo of the Canada 150 celebrations using an electron beam lithography system in the Quantum NanoFab facility at Waterloo.

“Canada 150 celebrates our past, present and future,” said Tobi Day-Hamilton, associate director of communications and strategic initiatives at IQC. “The future of Canadian technology is firmly set in the quantum world and at the nano-scale, so what better way to celebrate the lead up to 2017 than with a record-setting, nano-scale national flag.”

The record-setting flag was unveiled at IQC’s open house on September 17 [2016], which attracted nearly 1,000 visitors. It will also be on display in QUANTUM: The Exhibition, a Canada 150 Fund Signature Initiative, and part of Innovation150, a consortium of five leading Canadian science-outreach organizations. QUANTUM: The Exhibition is a 4,000-square-foot, interactive, travelling exhibit IQC developed highlighting Canada’s leadership in quantum information science and technology.

“I’m delighted that IQC is celebrating Canadian innovation through QUANTUM: The Exhibition and Innovation150,” said Raymond Laflamme, executive director of IQC. “It’s an opportunity to share the transformative technologies resulting from Canadian research and bring quantum computing to fellow Canadians from coast to coast to coast.”

The first of its kind, the exhibition will open at THEMUSEUM in downtown Kitchener on October 14 [2016], and then travel to science centres across the country throughout 2017.

You can find the English language version of QUANTUM: The Exhibition website here and the French language version of QUANTUM: The Exhibition website here.

There are currently four other venues for the show once finishes its run in Waterloo. From QUANTUM’S Join the Celebration webpage,


  • Science World at TELUS World of Science, Vancouver
  • TELUS Spark, Calgary
  • Discovery Centre, Halifax
  • Canada Science and Technology Museum, Ottawa

I gather they’re still looking for other venues to host the exhibition. If interested, there’s this: Contact us.

Other than the flag which is both nanoscale and microscale, they haven’t revealed what else will be included in their 4000 square foot exhibit but it will be “bilingual, accessible, and interactive.” Also, there will be stories.

Hmm. The exhibition is opening in roughly three weeks and they have no details. Strategy or disorganization? Only time will tell.