Title: The quantum spin Hall effect based on InAs/GaSb
Speaker: Prof. Rui-rui Du (Department of Physics and Astronomy, Rice University)
Time: 10:00(A.M.), Jun. 21, 2010
Venue: Academic Salon, Institute of Semiconductors, CAS
Abstract: The quantum Hall effect refers to the quantization of charge Hall resistance (in units of h/e2, where h is the Planck constant and e is the electronic charge), observed in a quantum well when an intense magnetic field is applied at low temperatures. The Quantum Spin Hall Effect (QSHE) is an emergent phenomenon recently discovered in semiconductors and other novel materials, where the intrinsic spin Hall conductance is quantized in the absence of any magnetic field. This talk will report on the experimental efforts in Rice University in low temperature quantum transport studies in InAs/GaAs quantum wells, in which an inverted band structure can be engineered and fine-tuning by electrostatic gates. We describe experimental results showing energy gap and edge transport in this system. The prospects for observing QSHE in this material and novel correlated properties, as predicted by recent theories, will be discussed.
About speaker：
Dr. Du’s research area and scholarly interests have been on the physics of low dimensional electron systems, especially on the fractional quantum Hall effect. The research work focuses on fundamental understanding of quantum mechanical properties of electrons in low dimensional and nanoscale semiconductor structures and devices. Here is an outline of current research topics. 2D and 1D electron systems provide both a clean laboratory for many-particle physics and a unique platform addressing emerging issues in spintronics and solid-state quantum information devices. Our recent research has been centered on these two themes and has been supported by DOE, NSF, and DARPA. The materials used are mainly GaAs/AlGaAs heterostructures and quantum wells, but also include Si and InGaAs depending on the physics involved.Title: The quantum spin Hall effect based on InAs/GaSb.