Excitation spectrum of Bilayer $ν=2$ Quantum Hall Systems

Yuichi Shimoda; Tatsuya Nakajima; Anju Sawada

doi:10.1016/j.physe.2003.11.215

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Excitation spectrum of Bilayer $ν=2$ Quantum Hall Systems

Yuichi Shimoda·Tatsuya Nakajima·Anju Sawada

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Abstract

Excitation spectra in bilayer quantum Hall systems at total Landau-level filling $ν=2$ are studied by the Hartree-Fock-Bogoliubov approximation. The systems have the spin degrees of freedom in addition to the layer degrees of freedom described in terms of pseudospin. On the excitation spectra from spin-unpolarized and pseudospin-polarized ground state, this approximation fully preserves the spin rotational symmetry and thus can give not only spin-triplet but also spin-singlet excitations systematically. It is also found that the ground-state properties are well described by this approximation.

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Yuichi Shimoda, Tatsuya Nakajima, Anju Sawada. 2003-07-31. Excitation spectrum of Bilayer $ν=2$ Quantum Hall Systems. https://doi.org/10.1016/j.physe.2003.11.215

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