Time Resolved Spectroscopy of InSb Quantum Wells Using Differential Transmission Technique

The growing interest in spin-related phenomena and devices has prompted intense activity in the science and engineering of narrow gap semiconductors (NGS). NGS offer several scientifically unique features such as small effective masses, large g-factors, high intrinsic mobilities, and large spin- orbit coupling effects. In this work we report the dynamics of photo-excited carrier/spin in several InSb/ Al$_{x}$In$_{1-x} $Sb based quantum wells (QWs) using differential transmission spectroscopy. The InSb QW layers were selectively pumped and probed by mid-infrared pulses to avoid possible contributions from the barrier materials. We compare our results with the earlier measurements using magneto-optical Kerr (MOKE) effect. Our results are important to understand different relaxation mechanisms in NGS with strong-spin orbit interactions.