The electron Hamiltonian of narrow semiconductor rings with the Rashba and Dresselhaus spin-orbit terms is invariant under a 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 wave functions 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.
|Physical Review B - Condensed Matter and Materials Physics
|Published - 2006
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics