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Effective Hamiltonian for striped and paired states at the half-filled Landau level

Nobuki Maeda
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Abstract

We study a pairing mechanism for the quantum Hall system using a mean field theory with a basis on the von Neumann lattice, on which the magnetic translations commute. In the Hartree-Fock-Bogoliubov approximation, we solve the gap equation for spin-polarized electrons at the half-filled Landau levels. We obtain an effective Hamiltonian which shows a continuous transition from the compressible striped state to the paired state. Furthermore, a crossover occurs in the pairing phase. The energy spectrum and energy gap of the quasiparticle in the paired state is calculated numerically at the half-filled second Landau level.

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Nobuki Maeda. 2000-11-30. Effective Hamiltonian for striped and paired states at the half-filled Landau level. https://doi.org/10.1016/s0550-3213(00)00713-6

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