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Variational study of the nu=1 quantum Hall ferromagnet in the presence of spin-orbit interaction

John Schliemann·J. Carlos Egues·Daniel Loss
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Abstract

We investigate the nu=1 quantum Hall ferromagnet in the presence of spin-orbit coupling of the Rashba or Dresselhaus type by means of Hartree-Fock-typed variational states. In the presence of Rashba (Dresselhaus) spin-orbit coupling the fully spin-polarized quantum Hall state is always unstable resulting in a reduction of the spin polarization if the product of the particle charge $q$ and the effective $g$-factor is positive (negative). In all other cases an alternative variational state with O(2) symmetry and finite in-plane spin components is lower in energy than the fully spin-polarized state for large enough spin-orbit interaction. The phase diagram resulting from these considerations differs qualitatively from earlier studies.

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John Schliemann, J. Carlos Egues, Daniel Loss. 2002-12-13. Variational study of the nu=1 quantum Hall ferromagnet in the presence of spin-orbit interaction. https://doi.org/10.1103/physrevb.67.085302

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