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Possible Jahn-Teller effect in Si-inverse layers

S. Brener·S. V. Iordanski·A. Kashuba
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Abstract

Jahn-Teller effect in bivalley Si(100) MOSFET under conditions of quantum Hall effect at integer filling factors nu=1,2,3 is studied. This system is described by SU(4) hidden symmetry. At nu=2 static and dynamic lattice deformation creates an easy-plane anisotropy and antiferromagnetic exchange and lifts the valley degeneracy. At nu=1,3 Coulomb interaction is essential to produce weak easy-plane anisotropy. Three phases: ferromagnetic, canted antiferromagnetic and spin-singlet, have been found. Anisotropy energy of charged skyrmion excitation in every phase is found.

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S. Brener, S. V. Iordanski, A. Kashuba. 2002-11-11. Possible Jahn-Teller effect in Si-inverse layers. https://doi.org/10.1103/physrevb.67.125309

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