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arXiv · 1911.08274

Observation and origin of the $\Delta$-manifold in Si:P $\delta$-layers

Ann Julie Holt·Sanjoy K. Mahatha·Raluca-Maria Stan·Frode S. Strand·Thomas Nyborg·Davide Curcio·Alex Schenk·Simon P. Cooil·Marco Bianchi·Justin W. Wells·Philip Hofmann·Jill A. Miwa
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Abstract

By creating a sharp and dense dopant profile of phosphorus atoms buried within a silicon host, a two-dimensional electron gas is formed within the dopant region. Quantum confinement effects induced by reducing the thickness of the dopant layer, from $4.0$\,nm to the single-layer limit, are explored using angle-resolved photoemission spectroscopy. The location of theoretically predicted, but experimentally hitherto unobserved, quantum well states known as the $\Delta$-manifold is revealed. Moreover, the number of carriers hosted within the $\Delta$-manifold is shown to be strongly affected by the confinement potential, opening the possibility to select carrier characteristics by tuning the dopant-layer thickness.

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Ann Julie Holt, Sanjoy K. Mahatha, Raluca-Maria Stan, Frode S. Strand, Thomas Nyborg, Davide Curcio, Alex Schenk, Simon P. Cooil, Marco Bianchi, Justin W. Wells, Philip Hofmann, Jill A. Miwa. 2019-11-19. Observation and origin of the $\Delta$-manifold in Si:P $\delta$-layers. https://doi.org/10.1103/physrevb.101.121402

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