Princeton University

School of Engineering & Applied Science

From Quantum Communications to Small Quantum Computers

Dr. Graeme Smith
E-Quad, B205
Thursday, February 26, 2015 - 4:30pm

Physical information carriers obey quantum laws.  Taking proper account of this fact has led over the past few decades to profound generalizations of both communication and computation theory.  First, I’ll discuss the central question in the theory of quantum communication: What are the capabilities of a noisy quantum communication link?  Addressing this question leads us to concepts like entanglement, a fundamentally quantum form of correlations which turns out to be a remarkably useful resource, new capabilities such as unconditionally secure cryptographic key agreement, and classically impossible kinds of synergy between independent communication links.  Second, I’ll discuss two key questions in the race to build a quantum computer: what can we do with a small quantum computer, and how can we know that we’ve done it?  These will be central questions in the coming decade as the size of quantum computing experiments begins to outstrip our capacity to do effective modeling on classical machines.

Graeme Smith is a research staff member at IBM’s TJ Watson Research Center in the physical sciences department.  He studies the fundamental limits that physics imposes on communication and computation, with a particular emphasis on protocols for overcoming or mitigating noise.  Specific research interests include quantum information theory and channel capacities, error correction, and robust quantum algorithms.  Graeme received a BSc in Physics from the University of Toronto and a PhD from the California Institute of Technology.