界面生长中断对GaAs(111)衬底上AlGaAs/GaAs量子阱电子自旋寿命的影响

Effect of Interface Growth Interruption on Spin Relaxation in GaAs(111)-AlGaAs/GaAs Quantum Wells

用固源分子束外延技术(SSMBE)在GaAs(111)衬底上,采用不同的界面中断时间生长了多组AlGaAs/GaAs多量子阱样品(MQWs),通过室温发光光谱和时间分辨克尔旋转谱(TRKR)研究了界面生长中断对发光光谱半峰全宽(FWHM)和量子阱中电子自旋弛豫时间(自旋寿命)的影响,发现了自旋寿命随着界面生长中断时间的增加呈现先减小后增加的趋势,此变化趋势与荧光光谱半峰全宽表征的材料质量随中断时间的变化一致,适当的界面生长中断时间能有效的增加GaAs(111)衬底上AlGaAs/GaAs多量子阱中电子自旋寿命。

The influence of interface growth interruption on electron spin relaxation time in AIGaAs/GaAs （111 ） multiple quantum wells （MQWs） grown by solid source molecular-beam epitaxy （SSMBE）, has been investigated by room temperature photoluminescence （PL） and time-resolved Kerr rotation spectroscopy （TRKR）. The interface roughness of quantum wells with different growth interruption time is studied by PL, and the results show that the full width at half maximum （FWHM） of PL spectra decrease with the growth in- terruption time to a minimum value then turn to increase with that. TRKR measurements at room temperature show that the appropriate growth interruption time can increase electron spin relaxation time in AlGaAs/GaAs QWs. Electron spin relaxation time and FWHM of PL spectra have the same variation tendency with growth interruption time. The electron spin relaxation time can be effectively increased at a proper interface interruption time. growth interruption time.