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Quantum Phase Fluctuations Responsible for Pseudogap

V. P. Gusynin·V. M. Loktev·R. M. Quick·S. G. Sharapov
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Abstract

The effect of ordering field phase fluctuations on the normal and superconducting properties of a simple 2D model with a local four-fermion attraction is studied. Neglecting the coupling between the spin and charge degrees of freedom an analytical expression has been obtained for the fermion spectral function as a single integral over a simple function. From this we show that, as the temperature increases through the 2D critical temperature and a nontrivial damping for a phase correlator develops, quantum fluctuations fill the gap in the quasiparticle spectrum. Simultaneously the quasiparticle peaks broaden significantly above the critical temperature, resembling the observed pseudogap behavior in high-T_c superconductors.

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V. P. Gusynin, V. M. Loktev, R. M. Quick, S. G. Sharapov. 2001-07-17. Quantum Phase Fluctuations Responsible for Pseudogap. https://doi.org/10.1016/s0921-4534(01)00950-9

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