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arXiv · 1510.00239

Electronic Structure, Transport and Phonons of SrAg$Ch$F ($Ch$=S, Se, Te): Bulk Superlattice Thermoelectrics

Vijay Kumar Gudelli·V. Kanchana·G. Vaitheeswaran·David J. Singh·A. Svane·N. E. Christensen·Subhendra D. Mahanti
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Abstract

We report calculations of the electronic structure, vibrational properties and transport for the p-type semiconductors, SrAg$Ch$F ($Ch$=S, Se and Te). We find soft phonons with low frequency optical branches intersecting the acoustic modes below 50 $cm^{-1}$, indicative of a material with low thermal conductivity. The bands at and near the valence band maxima are highly two dimensional, which leads to high thermopowers even at high carrier concentrations, which is a combination that suggests good thermoelectric performance. These materials may be regarded as bulk realizations of superlattice thermoelectrics.

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Vijay Kumar Gudelli, V. Kanchana, G. Vaitheeswaran, David J. Singh, A. Svane, N. E. Christensen, Subhendra D. Mahanti. 2015-10-01. Electronic Structure, Transport and Phonons of SrAg$Ch$F ($Ch$=S, Se, Te): Bulk Superlattice Thermoelectrics. https://doi.org/10.1103/physrevb.92.045206

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