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arXiv · 1812.04485

Dual quantum confinement and anisotropic spin splitting in the multi-valley semimetal PtSe$_2$

O. J. Clark·F. Mazzola·J. Feng·V. Sunko·I. Marković·L. Bawden·T. K. Kim·P. D. C. King·M. S. Bahramy
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Abstract

We investigate the electronic structure of a two-dimensional electron gas created at the surface of the multi-valley semimetal 1T-PtSe$_2$. Using angle-resolved photoemission and first-principles-based surface space charge calculations, we show how the induced quantum well subband states form multiple Fermi surfaces which exhibit highly anisotropic Rashba-like spin splittings. We further show how the presence of both electron- and hole-like bulk carriers causes the near-surface band bending potential to develop an unusual non-monotonic form, with spatially-segregated electron accumulation and hole accumulation regions, which in turn amplifies the induced spin splitting. Our results thus demonstrate the novel environment that semimetals provide for tailoring electrostatically-induced potential profiles and their corresponding quantum subband states

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O. J. Clark, F. Mazzola, J. Feng, V. Sunko, I. Marković, L. Bawden, T. K. Kim, P. D. C. King, M. S. Bahramy. 2019-02-25. Dual quantum confinement and anisotropic spin splitting in the multi-valley semimetal PtSe$_2$. https://doi.org/10.1103/physrevb.99.045438

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