The 383st forum: Structure behind chaos: Hidden information in fluctuation in small systems

Date: 2019-12-12
Time: 10:00
Venue: M830
Speaker: Prof. Siu-Tat Chui

Department of Physics and Astronomy, and Bartol Research Institute, University of Delaware

Prof. Siu-Tat Chui was born in Hong Kong, China. He went to McGill University in 1967 and obtained his B.S. degree with first class honors in physics in 1969. He won the first prize of the 1969 University Prize Exam sponsored by the Canadian Association of Physicists while in Canada. After that, he went to Princeton University on an Imperial Oil Fellowship and obtained a Ph.D. in physics in 1972. He remained an instructor at Princeton from 1972-73. He was a member of the Technical Staff at Bell Laboratories from 1973 to 1975, an Assistant Professor at SUNY-Albany from 1975 to 1979 and joined the Bartol Research Foundation in 1979 and is currently professor. He has been visiting professors at the University of Maryland, the Institute of Materials Research of Tohoku University, Japan; the Hong Kong University of Science and Technology, Umea University, Sweden and the Institute of Physics, Chinese Academy of Sciences, Beijing.

The exploration of the rich dynamics of electrons is a frontier in fundamental nano-physics. In conducting materials such as metals, the dynamical behavior of quasi-free electrons is dominated by random and chaotic thermal motion with ultrafast (~ps) and nanoscale scatterings. This generates inevitably fluctuating electromagnetic fields in close vicinity of the moving electrons. Here we study this fluctuation in small structures and found that its spatial distribution is not uniform, the magnitude of the fluctuation depends on external parameters such as the size (on the order of ~1 $\mu m$) and the shape of the structure and changes can occur by an order of magnitude. Our work opens the possibility of manipulating microscopic electron kinematics through nano-optical techniques and to applications in thermal detectors, photothermal photovoltaics and thermoelectricity.