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arXiv · 1606.00145

Tunable two-dimensional electron gas at the surface of thermoelectric material In$_4$Se$_3$

K. Fukutani·T. Sato·P. V. Galiy·K. Sugawara·T. Takahashi
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Abstract

We report the discovery of two-dimensional electron gas (2DEG) at the surface of thermoelectric material In$_4$Se$_3$ by angle-resolved photoemission spectroscopy. The observed 2DEG exhibits a nearly isotropic band dispersion with a considerably small effective mass of m* = 0.16 m_0, and its carrier density shows a significant temperature dependence, leading to unconventional metal-semiconductor transition at the surface. The observed wide-range thermal tunability of 2DEG in In$_4$Se$_3$ gives rise to additional degrees of freedom to better control the surface carriers of semiconductors.

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K. Fukutani, T. Sato, P. V. Galiy, K. Sugawara, T. Takahashi. 2016-06-01. Tunable two-dimensional electron gas at the surface of thermoelectric material In$_4$Se$_3$. https://doi.org/10.1103/physrevb.93.205156

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