Optical Response in Strained Type-II AlInAs/AlSb Ultrathin QW Heterostructure

AlSb/InAs heterostructure has a unique band alignment with a large conduction band offset finding application in a range of electronic devices. AlSb-based heterostructures have very recently been utilized for the fabrication of HEMTs, FETs, memories, and photodetectors. In this paper, the band structure, wave functions, dispersion curve, and optical gain of AlSb/AlInAs heterostructure have been reported. Kane 8 × 8 model with self-consistent calculations has been used to obtain the optical gain in type-II AlInAs/AlSb heterostructure as a function of 2D carrier injection. The peak TM optical gain at an energy of 0.652 eV is observed to be 1662 cm−1, while the peak TE optical gain is found to be 1271 cm−1 at an energy of 0.649 eV for a 2D charge carrier injection of 5 × 1012 cm−2. Further, a gradual blueshift is observed in the optical gain spectra as the 2D charge carrier injection is increased. The heterostructure has been found to operate in NIR, IR-B range with a high optical gain.