超长波GaAs/AlGaAs量子阱红外探测器光电流谱特性研究

研究了响应波长在15μm附近的超长波GaAs/AlGaAs量子阱红外探测器在不同外加偏压下的光电流谱特性.光电流谱上的两个主要由于阱宽随机涨落而呈现为高斯线形的响应峰被分别指认为量子阱基态E0到第一激发态E1和第三激发态E3的跃迁.跃迁峰随着器件上外加偏压的增大而出现线性红移现象，认为这种变化起源于激发态与基态对量子阱结构中势变化敏感性的不同，采用传输矩阵方法并考虑到电子交互作用修正进行的理论计算在定量上解释了实验结果. 关键词： 量子阱红外探测器 超长波 光电流 传输矩阵

Photocurrent spectra of very long wavelength GaAs/AlGaAs quantum well infrared photodetector

The photocurrent spectra characteristics of the 15μm very long wavelength GaAs/AlGaAs quantum well infrared photo detector(QWIP) have been investigated.The two photocurrent response peaks, which have a Gaussian lineshape due to the random fluctuation of the well width,are attributed to the transitions from the ground state E0 to the first excited state E１ and the third excited state E3 in the well,respectively.The transition peaks shift linearly to higher energy as the bias across the detector increases.Taking into account electrons exchange effect,we find that the theoretical calculation using the transfer matrix method agrees well with the experimental data.