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arXiv · 1504.05280

Off-resonant polarized light-controlled thermoelectric transport in ultrathin topological insulators

M. Tahir·P. Vasilopoulos
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Abstract

We study thermoelectric transport in ultrathin topological insulators under the application of circularly polarized off-resonant light of frequency Ω and amplitude A. We derive analytical expressions for the band structure, orbital magnetization Morb, and the thermal (\k{appa}xy) and Nernst (αxy) conductivities. Reversing the light polarization from right to left leads to an exchange of the conduction and valence bands of the symmetric and antisymmetric surface states and to a sign change in Morb,αxy, and \k{appa}xy. Varying the sample thickness or A/Ω leads to a strong enhancement of Morb and αxy. These effects, accessible to experiments, open the possibility for selective, state-exchanged excitations under light and the conversion of heat to electric energy.

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M. Tahir, P. Vasilopoulos. 2015-04-21. Off-resonant polarized light-controlled thermoelectric transport in ultrathin topological insulators. https://doi.org/10.1103/physrevb.91.115311

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