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arXiv · 1906.10162

Uncovering vacuum level in infinite solid by real-space potential-unfolding

Duk-Hyun Choe·Damien West·Shengbai Zhang
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Abstract

Although real materials are finite in size, electronic structure theory is built on the assumption of infinitely large solid, which led to a longstanding controversy: where is the vacuum level? Here, we introduce an analytic real-space potential-unfolding approach to uncover the vacuum level in infinitely large solid. First-principles calculations show that, in the absence of a physical surface, the bulk band structure, often measured with respect to an average bulk potential, is offset by a hereto unknown and orientation-dependent bulk quadrupole with respect to the vacuum level. By identifying intrinsic contributions of a bulk solid to its surface and interface properties, our theory eliminates the ambiguities surrounding the physical origin of the band alignment between matters.

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Duk-Hyun Choe, Damien West, Shengbai Zhang. 2019-06-24. Uncovering vacuum level in infinite solid by real-space potential-unfolding. https://doi.org/10.1103/physrevb.103.235202

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