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arXiv · 1911.05301

Effect of the polar distortion on the thermoelectric properties of GeTe

Aida Sheibani·Charles Paillard·Abhyian Pandit·Raad Haleoot·Laurent Bellaiche·Bothina Hamad
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Abstract

First principle calculations are performed to investigate the effect of polar order strength on the thermoelectric (TE) properties of GeTe alloy in its rhombohedral structure. The variation in the polarization state using various ferroelectric distortions {\lambda} ({\lambda}=0,0.5,1.0,1.25,1.5) allows to change the thermoelectric properties to a large extent. The polar structure with a high polarization mode ({\lambda}=1.5) tends to show a higher TE efficiency than the cubic structure at high temperatures. Thus, polarization engineering may play a key role in designing efficient thermoelectric devices. In particular, high TE performances could be achieved by growing epitaxial GeTe films that bi-axially compress the directions perpendicular to the polar axis, which may help to tune the Curie temperature.

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Aida Sheibani, Charles Paillard, Abhyian Pandit, Raad Haleoot, Laurent Bellaiche, Bothina Hamad. 2019-11-13. Effect of the polar distortion on the thermoelectric properties of GeTe. https://doi.org/10.1140/epjb%2Fs10051-020-00019-1

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