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Dynamical Properties in the Bilayer Quantum Hall Ferromagnet

Tatsuya Nakajima
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Abstract

The spectral functions of the pseudospin correlation functions in the bilayer quantum Hall system at ν=1 are investigated numerically, where the pseudospin describes the layer degrees of freedom. In the pseudospin-ferromagnetic phase, the lowest-energy excitation branch is closely connected with the ground state through the fluctuations of pseudospin S_y and S_z, and it plays a significant role on the tunneling properties in this system. For the system with very small tunneling amplitude and layer separation smaller than the critical one, the system-size dependence of calculated spectral function A_{y z} suggests the superfluidity on the tunneling current in the absence of impurities.

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Tatsuya Nakajima. 2001-02-26. Dynamical Properties in the Bilayer Quantum Hall Ferromagnet. https://doi.org/10.1103/physrevb.65.233317

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