Title

Light-Driven Electron Transport in   Molecular Junctions: Theory and Applications

Reporter

Prof. Liang-Yan Hsu

Reporter’s institution

Institute of Atomic and Molecular Sciences,   Academia Sinica

Report time

2018-12-10   11:00

Report location

Conference room on the 9th floor（9004）of Hefei National  Laboratory for Physical Sciences at the Microscale

Organizer

Hefei National Laboratory for Physical Sciences at the Microscale, International Center for Chemical Theory (ICCT), School of Chemistry and Materials Science

Report introduction

Abstract:

Electron transport through nanoscale systems such as   molecular junctions in the presence of coherent light is a fundamental subject in chemical physics and nanotechnology. In this talk, first, I would like to give a brief overview of quantum transport and introduce several key concepts in electron transport in a time-periodic (ac) field including   photon-assisted tunneling and coherent destruction of tunneling. To explore light-driven electron transport through molecules and quantum dots,Meir-Wingree-type formula is derived in the framework of single-particle Green’s functions together with non-Hermitian Floquet theory.In a two   terminal system, we investigate electron transport through aromatic hydrocarbon in a linearly polarized laser field and propose a new type of optoelectronic switch based on photon-assisted tunneling and destructive quantum interference. Moreover, several new concepts including   current-laser frequency characteristics,current-field amplitude  characteristics,and current-polarization angle  characteristics are introduced in this talk. In a three-terminal   system, a single-molecule optoelectronic router can be built by manipulating   the direction of a linearly polarized laser field. In a cross-conjugated   system, molecules with odd and even numbers of alkenyl groups  exhibit completely different current-polarization characteristics. If time permits, I will talk about my recent progress in photo-induced Coulomb   blockade and current fluctuation induced by molecular vibrations.
About the speaker:

Liang-Yan Hsu is an assistant research  fellow (faculty) of Institute of Atomic and Molecular Sciences of   Academia Sinica. He received his Ph.D. from Department of   Chemistry, Princeton University in 2015. After doing postdoctoral research at  Princeton University and at North Western University, he moved to Taipei and joined the faculty of Academia Sinica in 2017. His research interests include nanoelectronics (molecular electronics and 2D material electronics), methodology of quantum transport theory at the nanoscale,light-matter interactions at the nanoscale(plasmon-coupled exciton transfer and nonlinear spectroscopy),and high-order harmonic generation and ultrafast dynamics. Liang-Yan Hsu has published many important papers in high impact journals such as JACS, NanoLett., JPC Letters, etc.