On the Spin-Flip Mechanisms of Electrons in Semiconductor Quantum Wells

Abstract

We have studied the temperature dependence of the spin-flip processes of electrons in p-type modulation-doped GaAs quantum wells. We have found that at low temperature (T ≤ 30 K) the exchange interaction between electrons and holes is the main mechanism responsible for the spin-flip of the electrons, whereas at higher temperatures the so-called Dyakonov-Perel mechanism dominates. Furthermore, we have found that the recombination time increases considerably with increasing lattice temperature from a value of τr ≈︂ 200 ps at 5 K to τr ≈︂ 400 ps at 60 K.