Efficient Methods for the Characterization of Unknown
Quantum Processes

November 20, 2008 - 11:15-11:40am

RLE Conference Center 36-428

Abstract

The practical realization of quantum information devices and, ultimately, large-scale quantum computation, requires developing efficient methods to understand the coherent control limitations due to decoherence and other noise sources. I will give an overview of current work showing how simple and efficient randomization methods (that can already be applied in today's labs) provide crucial information about noisy quantum processes, such as the presence of spatial correlations, non-Markovian effects, and the relative probabilities of multi-qubit errors, that help assess the physical noise mechanisms, the effectiveness of quantum error correction protocols, the presence of noiseless subsystems, and the applicability of fault-tolerance threshold theorems.

Bio

Joseph obtained his B.Sc. in physics at McGill University, followed by a Master's degree in experimental physics and then a PhD in theoretical physics (2001), both from Simon Fraser University. The focus of his Ph.D. degree was quantum chaos and the quantum-classical correspondence for complex dynamical systems. After his Ph.D. Joseph took up a two year  post-doctoral position at MIT, followed by a two year post-doctoral fellowship at the Perimeter Institute for Theoretical Physics, where he studied the interface of randomness, decoherence, and quantum complexity, and developed seminal theoretical methods for understanding and overcoming the challenges confronting the practical implementation of quantum information algorithms. Joseph is currently a faculty member of the Department of Applied Mathematics at the University of Waterloo, a member of the Institute for Quantum Computing, and a scholar of the Canadian Institute for Advance Research. Joseph is actively working in the fields quantum information theory and quantum foundations, and he is spending the fall of 2008 as a visiting professor at MIT