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Phase transition and spin-wave dispersion in quantum Hall bilayers at filling factor nu=1

Anton Burkov·John Schliemann·A. H. MacDonald·S. M. Girvin
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Abstract

We present an effective Hamiltonian for a bilayer quantum Hall system at filling factor $ν=1$ neglecting charge fluctuations. Our model is formulated in terms of spin and pseudospin operators and is an exact representation of the system within the above approximation. We analyze its low-lying excitations in terms of spin-wave theory. Moreover we add to previous first-principle exact-diagonalization studies concentrating on the quantum phase transition seen in this system.

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Anton Burkov, John Schliemann, A. H. MacDonald, S. M. Girvin. 2001-08-12. Phase transition and spin-wave dispersion in quantum Hall bilayers at filling factor nu=1. https://doi.org/10.1016/s1386-9477(01)00299-5

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