arXiv subjects

Ann K. Rockwell

Publications and source records attributed to Ann K. Rockwell.

2 recordsLinked to original sources

arXiv2021

Full band Monte Carlo simulation of AlInAsSb digital alloys

Avalanche photodiodes fabricated from AlInAsSb grown as a digital alloy exhibit low excess noise. In this paper, we investigate the band structure-related mechanisms that influence impact ionization. Band-structures calculated using an empirical tight-binding method and Monte Carlo simulations reveal that the mini-gaps in the conduction band do not inhibit electron impact ionization. Good agreement between the full band Monte Carlo simulations and measured noise characteristics is demonstrated.

cond-mat.mtrl-sci↗

arXiv2021

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

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.

cond-mat.mtrl-sci↗