Quasi-two-dimensional thermoelectricity in SnSe

Abstract

Stannous selenide is a layered semiconductor that is a polar analogue of black phosphorus, and of great interest as a thermoelectric material. Unusually, hole doped SnSe supports a large Seebeck coefficient at high conductivity, which has not been explained to date. Angle resolved photo-emission spectroscopy, optical reflection spectroscopy and magnetotransport measurements reveal a multiple-valley valence band structure and a quasi two-dimensional dispersion, realizing a Hicks-Dresselhaus thermoelectric contributing to the high Seebeck coefficient at high carrier density. We further demonstrate that the hole accumulation layer in exfoliated SnSe transistors exhibits a field effect mobility of up to $250\mathrm{c}{\mathrm{m}}^2/Vs$ at $T=1.3\mathrm{K}$. SnSe is thus found to be a high quality, quasi two-dimensional semiconductor ideal for thermoelectric applications.

arXiv comment10 pages, 5 figures, plus supporting information

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Cited by in corpus (5)

• Review on thermoelectric properties of transition metal dichalcogenides
• Experimental formation of monolayer group-IV monochalcogenides
• Thermally-Enhanced Fröhlich Coupling in SnSe
• Ultrafast Photo-induced Phase Change in SnSe
• Direct observation of multiple conduction-band minima in high-performance thermoelectric SnSe