**U of G researchers explore precision and applications for quantum computing technology.**

Fans of Marvel’s *The Avengers* have heard of the quantum realm. In comics and films, the quantum realm is a dimension that exists at a microscopic scale, accessible by magical forces. Incredibly, it is not just the stuff of fantasy: quantum theory is an actual branch of physics dealing with atoms—basic units of matter made-up of subatomic particles called protons, neutrons, and electrons. Quantum information refers to properties found at the atomic scale. At that scale, the laws of physics as we know them don’t apply—particles exist in two places at once and even teleport. It is no wonder comic book artists went wild with imagination. And it is not just the artists and movie-goers who are fascinated. David Kribs, Rajesh Pereira, and Bei Zeng—the Quantum Information Group in the University of Guelph’s Mathematics and Statistics department—are conducting cutting-edge research that will help us understand and apply the mystifying properties found in the quantum realm.

Quantum computing is one of the most exciting applications of quantum information. Computers, in their simplest form, are calculators that store information as a sequence of zeroes and ones (“bits”). Conventional computers are efficient at tasks such as email and spreadsheets, but they struggle with large volumes of data and multi-step problems. Quantum computers, on the other hand, perform data operations by applying phenomena that occur on an atomic scale. Rather than bits, quantum computers use qubits, which can exist as zero, one, or in a state that represents both zero and one at the same time. This phenomenon is what enables quantum computers to perform certain computational tasks much faster than ordinary computers. However, there are challenges when it comes to manipulating quantum information with precision. Systems can break down due to environmental noise—factors like heat or impurities in the qubit material.

David Kribs and Rajesh Pereira have been working to understand quantum error correction problems like environmental noise with novel investigative methods that use mathematics-based tools and tricks from fancy math topics like matrix theory, operator algebras, and functional analysis.

“In practice, quantum computers have a threshold for noise—if they surpass that threshold, they will no longer be reliable—this is one reason why developing the theory of quantum error correction is so important,” Kribs explains.

Pereira expands: “Our investigations have allowed us to connect this topic with several rich areas of mathematics developed with purely mathematical motivations over the past century. For instance, we have recently applied graphic-theoretic techniques to a core problem in quantum communication.”

Bei Zeng, meanwhile, brought the theory into practice when she announced SpinQ Gemini, the first commercially available desktop quantum computer. These computers can demonstrate quantum algorithms and perform advanced model design. They are a low cost, light-weight option for users outside of big industry.

“We will pilot the first generation of SpinQ Gemini in several Canadian universities,” says Zeng. “Our vision is that SpinQ Gemini will be used in Quantum Computer courses all over the world.”

Like real-life superheroes, U of G’s Quantum Computing Group is exploring the mysterious quantum realm and transforming our understanding of the theory behind quantum computing, while also putting it into practice.