Department of Physics, Engineering Physics & Astronomy

Department of Physics, Engineering Physics & Astronomy
Department of Physics, Engineering Physics & Astronomy

Ultrafast Coherent Response in Photo-injected Biased Semiconductor Superlattice

Lijun Yang
Department of Physics, Queen's University

Tuesday, February 25, 2003
11:30 AM @ Stirling A

Abstract:

Over the past 15 years, considerable attention has been paid to the study of the dynamics of electrons and holes in biased semiconductor superlattices (BSSLs), coupled double quantum wells and other asymmetric quantum well structures. In this talk, I will present a brief introduction to BSSLs system. Both stationary states (Wannier Stark Ladder: WSL) and dynamic behavior (Bloch Oscillations: BO) of electron and holes in BSSLs will be introduced. The study of intraband polarization in BSSLs is essential to the understanding of the THz emission and Degenerate Four Wave Mixing signals produced by BSSLs excited by ultrashort optical pulses. The intraband polarization calculated by including only bound 1s exciton and its dependence on exciting laser frequency will be discussed. Some initial results of intraband polarization based on the inclusion of both bound and unbound excitonic states will also be investigated in the talk.