Opening of pseudogaps due to superconducting critical fluctuations in quasi-two dimensions

TL;DR

This paper investigates how anisotropic superconducting fluctuations in quasi-two-dimensional materials can lead to pseudogap formation, especially at high critical temperatures, by causing deviations from normal Fermi liquid behavior.

Contribution

It demonstrates that large anisotropy and high T_c induce pseudogaps through critical fluctuations, highlighting conditions where pseudogaps are prominent or absent.

Findings

Pseudogaps form due to critical fluctuations in highly anisotropic, high T_c superconductors.

Pseudogaps are absent or subtle in low T_c or isotropic three-dimensional superconductors.

Energy dependence of selfenergy deviates from Landau Fermi liquid in critical regions.

Abstract

We examine the role of the anisotropy of superconducting thermal critical fluctuations in the opening of pseudogaps in quasi-two dimensions. When the anisotropy of coherence or correlation lengths of the fluctuations is large enough and critical temperatures T_c are high enough, the energy dependence of the selfenergy deviates from that of Landau's normal Fermi liquid in critical regions; its imaginary part has no minimum at the chemical potential. Prominent pseudogaps open in such a non-Fermi liquid phase. Pseudogaps must be absent or subtle in quasi-two dimensional superconductors with low T_c and almost isotropic three dimensional superconductors.