Transient Faraday Rotation and Circular Dichroism Induced by Circularly‐Polarized Light in InGaN

Spin dynamics of InGaN is successfully examined with an optimized sample design and experimental conditions. Relaxation of spin initially created by a circularly‐polarized pump pulse is monitored by Faraday rotation and circular dichroism of a probe pulse at various wavelengths and temperatures. It is found that temporal decay consists of a fast and a slow components. Amplitude and decay time of the slow component have the second maximum against wavelength, which is related to band structures of InGaN. The fast and slow decay times are 1.1ps and 140ps at 10K, and decrease with temperature.