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Generalized Random-Phase Approximation Theory of Quasiparticle Spectral Functions: Application to Bilayer Quantum Hall Ferromagnets

Yogesh N. Joglekar·Allan H. MacDonald
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Abstract

We present a microscopic theory of ground-state spectral function of bilayer quantum Hall systems that includes interactions between Hartree-Fock quasiparticles and quantum fluctuations of the order parameter field. The collective modes in these systems are properly described only when fluctuations in direct and exchange particle-hole channels are taken into account. Using an auxiliary field functional integral approach, we present a generalization of the random phase approximation \emph{for quasiparticle self-energy} which captures fluctuations in both channels. We discuss its relationship to diagrammatic perturbation theory and an adiabatic approximation. We present simple analytical results for the quasiparticle self-energy and the renormalized order parameter that follow from this theory.

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Yogesh N. Joglekar, Allan H. MacDonald. 2001-08-04. Generalized Random-Phase Approximation Theory of Quasiparticle Spectral Functions: Application to Bilayer Quantum Hall Ferromagnets. https://arxiv.org/abs/cond-mat/0108077

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