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arXiv · 2105.13187

Characterization of band offsets in Al$_x$In$_{1-x}$As$_y$Sb$_{1-y}$ alloys with varying Al composition

Jiyuan Zheng·Andrew H. Jones·Yaohua Tan·Ann K. Rockwell·Stephen March·Sheikh Z. Ahmed·Catherine A. Dukes·Avik W. Ghosh·Seth R. Bank·Joe C. Campbell
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Abstract

The unprecedented wide bandgap tunability (~1 eV) of Al$_x$In$_{1-x}$As$_y$Sb$_{1-y}$ latticed-matched to GaSb enables the fabrication of photodetectors over a wide range from near-infrared to mid-infrared. In this paper, the valence band-offsets in AlxIn1-xAsySb1-y with different Al compositions are analyzed by tight-binding calculations and X-ray photoelectron spectroscopy (XPS) measurements. The observed weak variation in valence band offsets is consistent with the lack of any minigaps in the valence band, compared to the conduction band.

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Jiyuan Zheng, Andrew H. Jones, Yaohua Tan, Ann K. Rockwell, Stephen March, Sheikh Z. Ahmed, Catherine A. Dukes, Avik W. Ghosh, Seth R. Bank, Joe C. Campbell. 2021-05-27. Characterization of band offsets in Al$_x$In$_{1-x}$As$_y$Sb$_{1-y}$ alloys with varying Al composition. https://arxiv.org/abs/2105.13187

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