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arXiv · 0709.1457

What happens to geometric phase when spin-orbit interactions lift band degeneracy?

Philip B. Allen
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Abstract

Spin-orbit interaction lifts accidental band degeneracy. The geometric phase gamma(C)=pi for circuits surrounding a line of such degeneracy cannot survive completely unchanged. The change depends on how the spin is fixed during adiabatic evolution. For spin fixed along the internal spin-orbit field, gamma(C) decreases to zero as the circuit collapses around the line of lifted degeneracy. For spin fixed along a perpendicular axis, the conical intersection persists and gamma(C)=pi is unchanged.

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Philip B. Allen. 2007-09-10. What happens to geometric phase when spin-orbit interactions lift band degeneracy?. https://arxiv.org/abs/0709.1457

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