The incorporation of dilute concentrations of bismuth (Bi) into traditional III V alloys leads to significant reduction in bandgap energy, making InSbBi is a promising candidate for long wavelength infrared photodetection sensors due to its small bandgap (<0.17 eV). Furthermore, InSbBi could serve as a valuable platform for spin dynamics and quantum phenomena due to its strong spin-orbit coupling. Despite its potential, the material quality of InSbBi alloys lags behind that of conventional III V semiconductors, primarily due to the substantial challenges associated with incorporating Bi into InSb and producing high-quality InSbBi with varying Bi compositions. In this study, we address these issues by developing a method for growing smooth InSbBi thin films with tunable Bi incorporation up to 1.81% by the dynamic adjustment of Sb flux and careful control of the interplay between growth temperature and Bi flux using molecular beam epitaxy. This work paves the path for high-quality InSbBi thin films for applications in photodetection, spintronics, and quantum technology.
@article{arxiv.2503.11831,
title = {Evolution of surface morphology from Stranski Krastanov growth mode to step flow growth mode in InSbBi thin films},
author = {Chandima Kasun Edirisinghe and Anuradha Wijesinghe and Anjali Rathore and Pradip Adhikari and Christopher Rouleau and Joon Sue Lee},
journal= {arXiv preprint arXiv:2503.11831},
year = {2026}
}