Simulation of the band structure of InAs/GaSb type II superlattices utilizing multiple energy band theories

TL;DR

This paper reviews various theoretical methods for simulating the band structure of InAs/GaSb type II superlattices, aiming to aid in the design of these materials for infrared detection applications.

Contribution

It systematically compares and discusses modifications of multiple energy band theories for accurate simulation of InAs/GaSb superlattices.

Findings

Different methods have specific limitations and advantages.

Simulation methods have been improved for reliability.

Provides a reference for superlattice band structure design.

Abstract

Antimonide type II superlattices is expected to overtake HgCdTe as the preferred materials for infrared detection due to their excellent photoelectric properties and flexible and adjustable band structures. Among these compounds, InAs/GaSb type II superlattices represents the most commonly studied materials. However, the sophisticated physics associated with the antimonide-based bandgap engineering concept started at the beginning of 1990s gave a new impact and interest in development of infrared detector structures within academic and national laboratories. InAs/GaSb superlattices is a type II disconnected band structure with electrons and holes confined in the InAs and GaSb layers, respectively. The electron micro-band and hole micro-band can be regulated separately by adjusting the InAs and GaSb layers, which facilitates the design of superlattice structures and maximizes the amount of energy band offset. These works constituted a theoretical basis for the effective utilization of the InAs/GaSb system in material optimization and designing new SL structures; they also provided an opportunity for the preparation and rapid development of InAs/GaSb T2SLs. In this paper, we systematically review several widely used methods for simulating superlattice band structures, including the kp perturbation method, envelope function approximation, empirical pseudopotential method, empirical tight-binding method, and first-principles calculations. With the limitations of different theoretical methods proposed, the simulation methods have been modified and developed to obtain reliable InAs/GaSb SL energy band calculation results. The objective of this work is to provide a reference for designing InAs/GaSb type II superlattice band structures.