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arXiv · 1503.06224

The evaluation of non-topological components in Berry phase and momentum relaxation time in a gapped 3D topological insulator

Parijat Sengupta·Gerhard Klimeck·Enrico Bellotti
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Abstract

The zero gap surface states of a 3D-topological insulator host Dirac fermions with spin locked to the momentum. The gap-less Dirac fermions exhibit electronic behaviour different from those predicted in conventional materials. While calculations based on a simple linear dispersion can account for observed experimental patterns, a more accurate match is obtained by including higher order $ \overrightarrow{k}$ terms in the Hamiltonian. In this work, in presence of a time reversal symmetry breaking external magnetic field and higher order warping term, alteration to the topologically ordained Berry phase of $ (2n + 1)\pi $, momentum relaxation time, and the magneto-conductivity tensors is established.

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Parijat Sengupta, Gerhard Klimeck, Enrico Bellotti. 2015-03-20. The evaluation of non-topological components in Berry phase and momentum relaxation time in a gapped 3D topological insulator. https://doi.org/10.1088/0953-8984/27/33/335505

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