Comment on "Photon energy and carrier density dependence of spin dynamics in bulk CdTe crystal at room temperature"

TL;DR

This paper critiques a previous conclusion about spin relaxation mechanisms in bulk CdTe, emphasizing that the D'yakonov-Perel' mechanism dominates and confirming prior predictions about density dependence.

Contribution

It clarifies the dominant spin relaxation mechanism in bulk CdTe at room temperature, challenging prior claims and aligning with recent theoretical predictions.

Findings

D'yakonov-Perel' mechanism is the primary spin relaxation process.

Observed density dependence peak matches previous theoretical predictions.

Critiques the importance of Elliott-Yafet mechanism at high carrier densities.

Abstract

We comment on the conclusion by Ma et al. [Appl. Phys. Lett. {\bf 94}, 241112 (2009)] that the Elliott-Yafet mechanism is more important than the D'yakonov-Perel' mechanism at high carrier density in intrinsic bulk CdTe at room temperature. We point out that the spin relaxation is solely from the D'yakonov-Perel' mechanism. The observed peak in the density dependence of spin relaxation time is exactly what we predicted in a recent work [Phys. Rev. B {\bf 79}, 125206 (2009)].