Hole spin dephasing in $p$-type semiconductor quantum wells

Abstract

Hole spin dephasing time due to the D'yakonov-Perel' mechanism in $p$-type GaAs (100) quantum wells with well separated light-hole and heavy-hole bands is studied by constructing and numerically solving the kinetic spin Bloch equations. We include all the spin-conserving scattering such as the hole-phonon and the hole-nonmagnetic impurity as well as the hole-hole Coulomb scattering in our calculation. Different effects such as the temperature, the hole density, the impurity density and the Rashba coefficient on the spin dephasing are investigated in detail. We also show that the Coulomb scattering makes marked contribution to the spin dephasing. The spin dephasing time can either increase or decrease with temperature, hole/impurity density or the inclusion of the Coulomb scattering depending on the relative importance of the spin-orbit coupling and the scattering. It is also shown that due to the different spin-orbit coupling strengthes, many spin dephasing properties of holes are quite different from those of electrons.