On the pseudospin description of the electron Bloch bands

K. V. Samokhin

doi:10.1016/j.aop.2019.04.016

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arXiv · 1906.08106

On the pseudospin description of the electron Bloch bands

K. V. Samokhin

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Abstract

We study the transformation properties of the electron states in crystals with spin-orbit coupling, focusing primarily on the limitations of the frequently used pseudospin-1/2 description of twofold degenerate Bloch bands. Using the language of corepresentations of magnetic point groups, we construct the Bloch bases across the Brillouin zone in a way which is consistent with all symmetry requirements. This construction is applied to derive the effective spin-orbit Hamiltonians in noncentrosymmetric crystals, known as the generalized Rashba models, in both single-band and multiband cases.

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K. V. Samokhin. 2019-06-19. On the pseudospin description of the electron Bloch bands. https://doi.org/10.1016/j.aop.2019.04.016

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