Dave Touchette is a post-doctoral researcher at the Institute for Quantum Computing (IQC) and the Perimeter Institute for Theoretical Physics (PI). He collaborates with Ashwin Nayak, Debbie Leung, and Norbert Lütkenhaus on topics related to quantum information theory. In 2015, Dave moved from his hometown of Montreal, Quebec to Waterloo, Ontario with his partner, Valerie, and their first 2 children.
Dave began his studies at McGill University, where he completed an undergraduate degree in Mathematics and Physics. At McGill, he was drawn to information theory and learned about the broad reach of these ideas even in black hole physics. He went on to publish a paper with Kamil Bradler, Patrick Hayden, and Mark Wilde. Following this success, Dave joined Gilles Brassard and Alain Tapp at the Université de Montréal to pursue his PhD in Computer Science. At Montréal, he was taught quantum cryptography topics by researchers who helped to lay its foundations. Influenced by his work with Brassard and Tapp, Dave's research interests moved towards quantum communication complexity and interactive communication.
Following his studies, Dave moved to IQC because it is "one of the leading centres worldwide" in quantum information and features a concentration of top researchers like nowhere else. He was also attracted to PI’s reputation as a great environment for research in quantum information.
Dave’s research sits at the intersection of classical and quantum information theory. He says that this is an exciting time in information theory; there have been many important developments in recent years that do not yet have quantum counterparts.
To build on these developments, he studies the interactive and quantum counterparts of 2 big problems in information theory: the compression of low information-content messages, and the encoding of messages to overcome noisy communication channels.
His passion for research comes from the thrill of discovering new results and being on the frontier of knowledge. He likes that the tools he develops to solve problems might find applications in the future and help to build the foundation for future work. But for every discovery, there are many obstacles and dead-ends. His advice for young researchers is to focus on the future goals because the “excitement of getting somewhere more than makes up for the disappointments of setbacks.”
When not working on research problems, Dave enjoys spending time with his family. He believes that Waterloo is a good area to raise children because it has many parks and other things for children to do all in a safe environment. His 3rd child was born recently and he hopes to be able to secure a permanent research position near Québec so that his children can be close to their extended family.
 K. Bradler, P. Hayden, D. Touchette, M. M. Wilde, "Trade-off capacities of the quantum Hadamard channels," Physical Review A 81, 062312 (2010).
 M. Braverman, A. Garg, Y. K. Ko, J. Mao, D. Touchette, “Near-optimal bounds on bounded-round quantum communication complexity of disjointness,” IEEE 56th Annual Symposium on Foundations of Computer Science (FOCS) 2015, 773-791 (2015).