Yadav Nisha, Bhardwaj Garima, Anjum S G, Dalela S, Siddiqui M J, Alvi P A
Appl Opt. 2017 May 20;56(15):4243-4249. doi: 10.1364/AO.56.004243.
This paper reports a comprehensive theoretical study of W-shaped complex type-II InGaAs/InAs/GaAsSb nano-scale heterostructure consisting of two quantum wells of InAs material using the six-band k.p theory. The entire structure has been supposed to be grown on InP substrate. In order to optimize the optical gain, the probability densities of electrons and holes were optimized in the heterostructure. Following these calculations, dispersion relations for electron and hole energies, and transverse electric and transverse magnetic polarizations dependent dipole matrix elements and momentum matrix elements were calculated and, finally, the optical gain in both polarization modes was calculated. For this optimized complex heterostructure, a very high optical gain of the order of ∼4500 cm in the regime of mid-infrared wavelength ∼3.2 μm has been achieved. The results suggest that the designed nano-heterostructure may be utilized for mid-infrared region (MIR) applications such as chemical and bio-molecular sensing of molecules, for the applications of spectroscopy in the "fingerprint region" of molecular science, and for detection of atmospheric gases that respond to 3.2 μm wavelength.
本文报道了一项使用六带k.p理论对由两个InAs材料量子阱组成的W形复合型II型InGaAs/InAs/GaAsSb纳米级异质结构进行的全面理论研究。整个结构假定生长在InP衬底上。为了优化光学增益，在异质结构中对电子和空穴的概率密度进行了优化。经过这些计算，计算了电子和空穴能量的色散关系、依赖于横向电偏振和横向磁偏振的偶极矩阵元和动量矩阵元，最后计算了两种偏振模式下的光学增益。对于这种优化后的复合异质结构，在中红外波长约为3.2μm的范围内实现了约4500 cm的非常高的光学增益。结果表明，所设计的纳米异质结构可用于中红外区域（MIR）的应用，如分子的化学和生物分子传感、分子科学“指纹区域”的光谱学应用以及对3.2μm波长有响应的大气气体检测。
