摘要
报道不同层厚的ＡｌＡｓ／ＡｌｘＧａ１－ｘＡｓ及ＧａＡｓ／ＡｌｘＧａ１－ｘＡｓ短周期超晶格的纵光学声子模的室温喇曼散射测量结果．在非共振条件下，观察到ＡｌＡｓ／ＡｌｘＧａ１－ｘＡｓ中限制在ＡｌｘＧａ１－ｘＡｓ混晶层中的类ＧａＡｓＬＯ限制模和限制在ＡｌＡｓ层中的ＡｌＡｓＬＯ限制模，还观察到ＧａＡｓ／ＡｌｘＧａ１－ｘＡｓ中限制在ＡｌｘＧａ１－ｘＡｓ混晶层中的类ＡｌＡｓＬＯ限制模和限制在ＧａＡｓ层中的ＧａＡｓＬＯ限制模．在近共振条件下，还观察到了ＡｌＡｓ／ＡｌｘＧａ１－ｘＡｓ中ＡｌＡｓ的界面模．根据线性链模型，把测量的ＬＯ限制模的频率按照ｑ＝ｍｎ＋１２πα０展开，给出了ＡｌｘＧａ１－ｘＡｓ混晶的类ＡｌＡｓ支和类ＧａＡｓ支光学声子色散曲线．
The room temperature Raman scattering studies of longitudinal optic phonons in AlAs/Al x Ga 1- x As and GaAs/Al x Ga 1- x As short period superlattices with different layer thicknesses were reported. The AlAs LO modes confined in AlAs layers and GaAs like LO modes confined in Al x Ga 1- x As layers were observed in AlAs/Al x Ga 1- x As superlattices under off resonance conditions. And the GaAs LO modes confined in GaAs layers and AlAs like LO modes confined in Al x Ga 1- x As layers were observed in GaAs/Al x Ga 1- x As superlattices.In addition, the AlAs interface mode in AlAs/Al x Ga 1- x As was also observed under near resonance conditions. Based on the linear chain mode, the frequencies of confined LO modes measured by Raman scattering were unfolded according to q=mn+12πα 0 , by which the dispersion curves of AlAs like and GaAs like LO phonons in Al x Ga 1- x As mixed crystal were obtained.
出处
《红外与毫米波学报》
SCIE
EI
CAS
CSCD
北大核心
1999年第3期189-194,共6页
Journal of Infrared and Millimeter Waves
