Tunable bandgap and isotropic light absorption from bismuth-containing GaAs core–shell and multi-shell nanowires

Abstract

Semiconductor core–shell nanowires based on the GaAs substrate are the building blocks of many photonic, photovoltaic and electronic devices, thanks to their associated direct bandgap and highly tunable optoelectronic properties. The selection of a suitable material system is crucial for custom designed nanowires tailored for optimised device performance. Bismuth-containing GaAs materials are an imminent class of semiconductors which not only enable an exquisite control over the alloy strain and electronic structure but also offer the possibility to suppress internal loss mechanisms in photonic devices. Whilst the experimental efforts to incorporate GaBixAs1−x alloys in the nanowire active r..