Electron spin relaxation time τs in InGaAs/InAlAs quantum wells (QWs) grown on (110) and (100) InP substrates was investigated by pump-probe transmission measurements. Similar τs of 0.83-1.0ns were measured at room temperature for all the measured (110) and (100) QWs, indicating suppression of the D'yakonov-Perel' spin relaxation mechanism in (110) QWs is not effective in InGaAs/InAlAs QWs as opposed to GaAs/AlGaAs QWs. Contribution of the Bir-Aronov-Pikus mechanism dominant in (110) GaAs/AlGaAs QWs was found to be small in both the (110) and (100) InGaAs/InAlAs QWs from the weak dependences of τs on pump intensity at room temperature. These results suggest that the spin relaxation mechanism dominant in InGaAs/InAlAs QWs at a temperature higher than 200K is the Elliott-Yafet mechanism independent of the crystal orientation among the above three major mechanisms.
ASJC Scopus subject areas
- Physics and Astronomy(all)