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DOE OSTI · 2998292

Imaging the Acceptor Wave Function Anisotropy in Silicon

Siegl, Manuel [Univ. College London (United Kingdom)]·Zanon, Julian [Eindhoven Univ. of Technology (Netherlands)] (ORCID:0000000228301361)·Sink, Joseph [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000249691565)·Rodrigues da Cruz, Adonai [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:000000018719399X)·Hedgeland, Holly [Univ. College London (United Kingdom)] (ORCID:0000000337037942)·Curson, Neil J. [Univ. College London (United Kingdom)] (ORCID:0000000256610559)·Flatté, Michael E. [Eindhoven Univ. of Technology (Netherlands)] (ORCID:0000000150931549)·Schofield, Steven R. [Univ. College London (United Kingdom)] (ORCID:0000000207273015)
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Abstract

We present the first scanning tunneling microscopy (STM) image of hydrogenic acceptor wave functions in silicon. These acceptor states appear as square-ring-like features in STM images and originate from near-surface defects introduced by high-energy bismuth implantation into a silicon (001) wafer. Scanning tunneling spectroscopy confirms the formation of a p-type surface. Effective-mass and tight-binding calculations provide an excellent description of the observed square-ring-like features, confirming their acceptor character and attributing their symmetry to the light- and heavy-hole band degeneracy in silicon. A detailed understanding of the energetic and spatial properties of acceptor wave functions in silicon is essential for engineering large-scale acceptor-based quantum devices.

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77 NANOSCIENCE AND NANOTECHNOLOGYacceptor stateseffective-mass theoryquantum device engineeringscanning tunneling microscopysilicontight binding Green’s functions

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Siegl, Manuel [Univ. College London (United Kingdom)], Zanon, Julian [Eindhoven Univ. of Technology (Netherlands)] (ORCID:0000000228301361), Sink, Joseph [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:0000000249691565), Rodrigues da Cruz, Adonai [Univ. of Iowa, Iowa City, IA (United States)] (ORCID:000000018719399X), Hedgeland, Holly [Univ. College London (United Kingdom)] (ORCID:0000000337037942), Curson, Neil J. [Univ. College London (United Kingdom)] (ORCID:0000000256610559), Flatté, Michael E. [Eindhoven Univ. of Technology (Netherlands)] (ORCID:0000000150931549), Schofield, Steven R. [Univ. College London (United Kingdom)] (ORCID:0000000207273015). 2025-08-21. Imaging the Acceptor Wave Function Anisotropy in Silicon. https://doi.org/10.1021/acs.nanolett.5c02675

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