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Degenerate states of narrow semiconductor rings in the presence of spin orbit coupling: Role of time-reversal and large gauge transformations

S. -R. Eric Yang
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Abstract

The electron Hamiltonian of narrow semiconductor rings with the Rashba and Dresselhaus spin orbit terms is invariant under time-reversal operation followed by a large gauge transformation. We find that all the eigenstates are doubly degenerate when integer or half-integer quantum fluxes thread the quantum ring. The wavefunctions of a degenerate pair are related to each other by the symmetry operation. These results are valid even in the presence of a disorder potential. When the Zeeman term is present only some of these degenerate levels anticross.

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S. -R. Eric Yang. 2006-08-16. Degenerate states of narrow semiconductor rings in the presence of spin orbit coupling: Role of time-reversal and large gauge transformations. https://doi.org/10.1103/physrevb.74.045315

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