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arXiv · 1312.3879

Measure of Diracness in two-dimensional semiconductors

M. O. Goerbig·G. Montambaux·F. Piéchon
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Abstract

We analyze the low-energy properties of two-dimensional direct-gap semiconductors, such as for example the transition-metal dichalcogenides MoS$_2$, WS$_2$, and their diselenide analogues MoSe$_2$, WSe$_2$, etc., which are currently intensively investigated. In general, their electrons have a mixed character -- they can be massive Dirac fermions as well as simple Schrödinger particles. We propose a measure (Diracness) for the degree of mixing between the two characters and discuss how this quantity can in principle be extracted experimentally, within magneto-transport measurements, and numerically via ab initio calculations.

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M. O. Goerbig, G. Montambaux, F. Piéchon. 2014-03-06. Measure of Diracness in two-dimensional semiconductors. https://doi.org/10.1209/0295-5075%2F105%2F57005

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