摘要
用垂直入射的中红外光束调制非掺杂SiGe Si量子阱中光致子带间吸收 .氩离子激光器作为子带间跃迁的光泵浦源在阱中产生载流子 ,红外调制光谱用步进式傅立叶变换光谱仪记录 .实验中观察到明显的层间干涉效应及与子带间跃迁有关的色散效应 .理论和实验分析认为样品折射率变化造成的位相调制可以补偿吸收所造成的幅度调制 .
Modulation of mid-infrared beam by photo-induced intersubband absorption in undoped SiGe/Si quantum wells was investigated at normal incidence. An Ar+ laser is used as optcal pumping of interband transitions to photocreate carriers in the wells. The modulated transmission of the sample was measured by a step-scan Fourier transform spectroscopy. Resonant dispersion associated with intersubband transitions and mutiple reflections effect in the mufti-quantum wells were clearly evidenced. Theoretical and experimental results show that the phase modulation due to refractive index variations may compensate for amplitude modulation due to absorption.
出处
《红外与毫米波学报》
SCIE
EI
CAS
CSCD
北大核心
2002年第2期87-90,共4页
Journal of Infrared and Millimeter Waves
基金
国家教育部留学回国人员科研启动基金资助项目~~
