Response to 'Comment on 'Photon energy and carrier density dependence of spin dynamics in bulk CdTe crystal at room temperature' ' [Appl. Phys. Lett. 136101 (2010)]

摘要

In our previous paper, carrier density and photon energy dependence of electron spin relaxation in CdTe crystal were investigated by time-resolved pump probe reflectivity method at room temperature. It was found that the spin relaxation time constant varies nonmonotonously with carrier density; the spin lifetime shows a maximum at the carrier density of about 2.86 × 10~(11) cm~(-2). Our experimental finding is different from previous report in an intrinsic GaAs, in which spin lifetime increases linearly with the carrier density due to D'yakonov-Perel (DP) mechanism dominating the spin relaxation process. Based on elastic-scattering approximation, we inferred that there is an additional mechanism contributing to the electron spin relaxation at higher carrier concentration. Therefore, Elliott-Yafet mechanism was proposed to contribute to the spin relaxation at high carrier concentration.