Tutte Colloquium - Debbie Leung

Friday, September 29, 2017 3:30 pm - 3:30 pm EDT (GMT -04:00)

Title: The quantum and private capacities of quantum channels, and the solution in the low-noise regime

Speaker: Debbie Leung
Affiliation: University of Waterloo
Room: MC 5501


We first summarize background on the quantum capacity of a quantum channel, and explain why we know very little about this fundamental quantity, even for the qubit depolarizing channel (the quantum analogue of the binary symmetric channel) despite 20 years of effort by the community.
Then, we focus on low-noise quantum channels, and discuss recent results on the quantum capacity to leading orders in the noise parameter. This in particular solves the quantum capacity problem (to leading orders) for the qubit depolarizing channel, and provides a structure theorem for the capacity achieving codes.
Analogous results on the private capacity will be presented.
Joint work with Felix Leditzky and Graeme Smith.