Australian Institute of Physics - ‘Women in Physics Lecture Tour’ 2024

Stochastic resonance, where noise synchronizes a system’s response to an external drive, is a phenomenon that occurs in a wide variety of noisy systems ranging from the dynamics of neurons to the periodicity of ice ages. This talk will present theory and experiments on a quantum system that exhibits stochastic resonance; the quantum tunneling of the magnetization of a single Fe atom measured using spin-polarized scanning tunneling microscopy. Stochastic resonance is shown deep in the quantum regime, where fluctuations are driven by tunneling of the magnetization, as well as in a semi-classical crossover region where thermal excitations set in. It is then shown that stochastic resonance can be exploited to gain new insight into the high-frequency dynamics of nanoscale systems.

Susan Coppersmith, a theoretical condensed matter physicist, received her PhD from Cornell University, performed postdoctoral work at Brookhaven National Laboratories and AT&T Bell Laboratories, and was a visiting lecturer at Princeton University.  She was a Distinguished Member of Technical Staff at AT&T Bell Laboratories in Murray Hill, New Jersey (USA), a Professor at the University of Chicago, and a Professor and Department Chair at the University of Wisconsin-Madison.  She is currently a Scientia Professor of Physics and the Head of the School of Physics at UNSW Sydney in Sydney, Australia.

Dr. Coppersmith’s research has focused on a variety of complex condensed matter systems driven far from thermal equilibrium.  Over the past two decades a major research focus has been on the development of quantum computers using silicon quantum dots. 

Dr. Coppersmith has served as Chair of the Condensed Matter and Materials Research Committee of the National Research Council of the US, as Chair of the Division of Condensed Matter Physics and of the Topical Group for Statistical and Nonlinear Physics of the American Physical Society, as Chair of the Section on Physics of the American Association for the Advancement of Science, and as Chair of the Board of Trustees of the Gordon Research Conferences.

Dr. Coppersmith has been elected to be a Fellow of the Australian Academy of Science, the American Association for the Advancement of Science, the American Academy of Arts and Sciences, and the National Academy of Sciences.