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arXiv · cond-mat/0202010

Renormalization group approach to the interacting boson fermion systems

T. Domanski·J. Ranninger
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Abstract

We study a pseudogap region of the mixed boson fermion system using a recent formulation of the renormalization group technique through the set of infinitesimal unitary transformations. Renormalization of fermion energies gives rise to a depletion of the low energy states (pseudogap) for temperatures $T^{*}>T>T_{c}$ which foreshadows appearance of the pairwise correlations with their long range phase coherence being missed. With a help of the flow equations for boson and fermion operators we analyze spectral weights and finite life times of these quasiparticles caused by interactions.

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T. Domanski, J. Ranninger. 2002-02-01. Renormalization group approach to the interacting boson fermion systems. https://arxiv.org/abs/cond-mat/0202010

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