Temperature-and Composition-Dependent Band Gap Energy and Electron-Phonon Coupling in InAs1-xSbx Semiconductors Alloys for Infrared Photodetection

This paper makes an improvement on the determination of the temperature, bowing parameter, and antimony (Sb) composition effects on the fundamental band gap energy of InAs1-xSbx ternary alloys for infrared (IR) photodetection. The present study was carried out in a broader temperature range from cryogenic to room temperature for the entire alloy range, and a reasonable analysis has also been carried out. Meanwhile, a proposed expression for the band gap bowing parameter temperature dependence has been established. The optical cut-off wavelength can be further tuned over a significant range up to 14 mu m or more by altering the stoichiometry of InAs1-xSbx alloys. The three Varshni and Bose-Einstein thermodynamic parameters were found to exhibit a parabolic trend with Sb composition. Consequently, the quadratic equations relating these parameters to Sb composition were derived. The relatively weak band gap temperature coefficient reported here is hoped to offer an improvement on infrared photodetector (IR-PD) stability. Also, the average phonon energy and the corresponding electron-phonon coupling interaction strength were investigated versus Sb composition. The available experimental results were used, where possible, to confirm our theoretical estimates, and the agreement is satisfactory. We expect that the present work will be helpful in designing and improving the photodetection properties of IR optoelectronics devices. Additionally, it provides a firm basis for our forthcoming determination of the electronic band structure properties of InAs1-xSbx based superlattices. [GRAPHICS]

Automated summary

This paper improves the understanding of the temperature, bowing parameter, and antimony composition effects on the band gap energy of InAs1-xSbx alloys. The study includes a broad temperature range and provides reasonable analysis. The results show that the band gap can be tuned by altering the stoichiometry, and the thermodynamic parameters exhibit a parabolic trend with Sb composition. The findings have implications for improving infrared photodetectors and designing optoelectronics devices.