摘要
采用固态源分子束外延的方法在GaAs(110)取向衬底上生长了GaAs/Al GaAs多量子阱结构.对样品进行了低温光致发光谱和时间分辨光致发光谱的测量,结果表明激发功率和激发波长对室温下量子阱内电子的自旋弛豫时间有强烈的影响.对于常见的GaAs(100)量子阱起支配作用的D'yakonov-Perel'(DP)自旋弛豫机制,在GaAs(110)量子阱材料里被充分地抑制了.对于缺失了DP相互作用的GaAs(110)多量子阱,电子-空穴相互作用对自旋弛豫时间随激发功率变化有重要的影响.
GaAs/A1GaAs （110） multiple quantum wells （MQWs） were grown by solid source molecular beam epitaxy （MBE） with a valved arsenic cracker cell. The optical properties of the undoped GaAs （110） MQWs were studied by low-tempera-ture photolurninescence and time-resolved photoluminescence （TRPL）, which show that a strong electron spin relaxation dy-namic is dependent on the excitation power and wavelength at room temperature. In this material, the predominant spin scattering mechanism [D＇yakonov-Perel＇（DP） mechanism] for conventional （100） QWs is substantially suppressed. The ex-periment data indicate that the electron-hole exchange interaction has a great impact on the spin relaxation time in GaAs （110） MQWs at room temperature.
基金
国家自然科学基金(批准号:10504030)
中国科学院知识创新工程和甘肃省自然科学基金(批准号:3ZS051-A25-034)资助项目~~
关键词
电子自旋弛豫
多量子阱
分子束外延
electron spin relaxation
multiple quantum wells
molecular beam epitaxy
