Electron Spin-relaxation Dynamics in GaAs/AlGaAs Quantum Wells and InGaAs/InP Quantum Wells

We have investigated the spin-relaxation process of electrons at room temperature in undoped GaAs/AlGaAs multiple-quantum wells (MQWs) and InGaAs/InP MQWs. The spin-relaxation times are measured for different well thicknesses using time-resolved spin-dependent pump and probe absorption measurement. The spin-relaxation time, τ s , for GaAs MQWs was found to depend on the electron confinement energy, E 1e , according to τ s ∝ E 1e -2.2 ,...