Photocurrent spectra of heavily doped terahertz quantum well photodetectors
Photocurrent spectra of heavily doped terahertz quantum well photodetectors
复制标题
DOI：
10.1063/1.3458829
复制
发表时间：
2010-07
影响因子：
4
通讯作者：
X. G. Guo;Riqing Zhang;H. Liu;A. Springthorpe;Juncheng Cao
中科院分区：
文献类型：
--
作者：
X. G. Guo;Riqing Zhang;H. Liu;A. Springthorpe;Juncheng Cao
太赫兹(THz)量子井光探测器是太赫兹成像和太赫兹自由空间通信的重要候选材料。太赫兹量子阱的吸收效率低是限制此类太赫兹探测器性能的主要因素。为了提高吸收效率，我们制作了三个重掺杂的太赫兹量子阱。能带结构计算表明，随着Si掺杂浓度的增加，第二子带进入量子阱，从而降低了第二子带中光子激发电子的逃逸几率。这是随着Si掺杂量的增加，光电流峰蓝移和展宽的原因。
Terahertz (THz) quantum well photodetectors (QWPs) are an important candidate for THz imaging and THz free space communication. Low absorption efficiency of THz QWPs is the main factor limiting the performance of this kind of THz detectors. To increase the absorption efficiency, three heavily doped THz QWPs were fabricated. The band structure calculations show that the second subband falls into the quantum well with increasing Si doping concentration, which decreases the escape probability of the photon-excited electrons in the second subband. This effect is responsible for the blueshift and broadening of the photocurrent peak with increasing Si doping.