Abstract

 

In light of the growing interest in spin-related phenomena and devices, there is now renewed interest in the science and engineering of narrow gap semiconductors.   Narrow gap semiconductors offer several unique features such as small effective masses, large effective g -factors, high intrinsic mobilities, and large spin-orbit coupling effects.   This talk will discuss magneto-optical studies on InSb quantum wells (QWs) and ferromagnetic semiconductors such as InMnAs and InMnSb.   In InSb QWs, we observe spin-resolved cyclotron resonance (CR) caused by the non-parabolicity of the conduction band and electron spin resonance in symmetric and asymmetric confinement potentials.   The asymmetric wells exhibit a strong deviation in behavior from the symmetric wells at low magnetic fields with far more spin splitting than expected from the bulk g -factor of InSb.   In addition, in order to increase our understanding of the dynamics of carriers and spins, we performed several time-resolved measurements such as magneto-optical Kerr effect.   Our results are important for understanding the electronic and magnetic states in narrow gap semiconductors.

 

Biography

Dr. Giti Khodaparast is an Assistant Professor at the Physics Department, Virginia Tech. She got her PhD degree from University of Oklahoma in 2001. From 2001 to 2004, she had been a Postdoctoral Research Associate, Rice University, Houston, Texas. Prof. Khodaparast’s field of research is Experimental Condensed Matter Physics. Her current research interests are in: optical, infrared and far-infrared spectroscopy of solids; ultrafast and nonlinear optics; terahertz dynamics and device applications; spin-dependent phenomena and device applications; application of nano-particles in biology. She had been an active user at Stanford Picosecond Free Electron Laser Center, Stanford, California, and Megagauss Laboratory, University of Tokyo, Japan. She is currently an active user at the National High Magnetic Field Laboratory, Tallahassee, Florida.