Large Fluctuations in Systems Lacking Time-reversal Symmetry

Michigan State University, East Lansing MI

Investigators

Abstract

0071059 Dykman Large fluctuations give rise to many important physical phenomena, from radioactive decay to nucleation in phase transitions and to protein folding. The goal of the proposed research is to develop appropriate mathematical tools and investigate large quantum and classical fluctuations in systems which lack time-reversal symmetry. The problems of specific interest are single- and many-electron tunneling in a magnetic field, including tunneling from correlated two-dimensional electron systems, and escape from a metastable state of nonequilibrium classical and quantum systems, including systems driven by periodic fields. Breaking of time-reversal symmetry results in the occurrence of singularities in the pattern of optimal fluctuational paths. The singularities are expected to have common features in classical and quantum systems. Revealing these features is necessary for evaluating fluctuation probabilities and finding efficient ways of controlling them by external fields. Theoretical results will be compared with experimental data. The goal of the research is to develop theoretical methods of the analysis of large fluctuations in quantum and classical systems lacking time-reversal symmetry, and to investigate related new physical effects. Although the research is fundamental, its results bear on several applications. It is immediately related to using large fluctuations as a diagnostic tool and controlling fluctuation probabilities. Concurrent interest and growing body of experimental work on large fluctuations in different areas of physics, chemistry, and biology make the project particularly timely.