Non-Fermi liquid behaviour and superconductivity in the dissipative model

P. C. Howell; A. J. Schofield

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arXiv · cond-mat/0103191

Non-Fermi liquid behaviour and superconductivity in the dissipative model

P. C. Howell·A. J. Schofield

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Abstract

We study an exactly-solvable model which shows a zero-temperature transition from a non-Fermi liquid to a Fermi liquid as a function of particle density. The quantum critical point separating these two states is not associated with the usual ordering transition of a bosonic degree of freedom. We analyze the properties of this critical point in terms of an effective density of states, and we use this concept to generalize this transition to a class of related quantum critical points. We study the superconducting instability of the low-density (non-Fermi liquid) regime and we show that it has an enhanced pair susceptibility relative to the Fermi liquid. We comment on the applicability of our results to low-carrier density superconductors.

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P. C. Howell, A. J. Schofield. 2001-03-08. Non-Fermi liquid behaviour and superconductivity in the dissipative model. https://arxiv.org/abs/cond-mat/0103191

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