Spin-relaxation in an InGaAs/InP MQW

Abstract

Room temperature picosecond pump-probe transmission measurements on InGaAsP/InGaAsP MQWs have shown large rotation (~40°) of probe polarisation induced by circularly polarised pump. We report low temperature investigations in a lattice matched In0.43Ga0.57As/InP MQW 8nm wide which does not reproduce this remarkable effect. Our measurements were made with an all-solid-state optical parametric oscillator tunable from 1.2 to 6µm. The non-linear crystal is periodically poled lithium niobate fabricated at Southampton, pumped synchronously by a modelocked, diode pumped Nd:YLF laser