GaAs/AlGaAs异质结的微波调制反射谱(英文)

Microwave-modulated reflectance spectroscopy in the GaAs/AlGaAs heterostructure

基于搭建的微波调制反射谱测量系统(MMRS),确定了GaAs/AlGaAs异质结构中价带空穴到二维电子系统(2DES)电子基态(GS)的跃迁.微波调制反射谱与温度的依赖关系表明,随着测量温度的升高,能带带隙发生了蓝移现象;而其与磁场的依赖关系表明,随着测量磁场的增大,能带带隙则发生了红移现象;它们均与GaAs/AlGaAs异质结构中价带空穴的带填充效应有关.基于Kramers-Kronig关系的理论模拟给出了和实验测量相似的结果.

A microwave-modulated reflectance spectroscopy（MMRS） measurement system was constructed.This MMRS technique was used to identify a transition from holes in valence band to electrons in the ground subband（GS） of the two-dimensional electron system（2DES） formed in a GaAs/AlGaAs heterostructure sample.The temperature（T） dependence of the MMRS shows a blue shift of the energy gap with increasing T,while the magnetic field（B） dependence of the MMRS shows a red shift of the energy gap with increasing B.Both phenomena are attributed to the band-filling effect of holes in valence band in the GaAs/AlGaAs heterostructure.A theoretical simulation based on Kramers-Kronig relation was also presented which was similar with the experimental data.