Non-Fermi liquid and pairing in electron-doped cuprates

TL;DR

This paper investigates the non-Fermi liquid behavior and unconventional pairing mechanisms in electron-doped cuprates, revealing how Fermi surface curvature influences superconducting transition temperature and gap structure, aligning with experimental observations.

Contribution

It demonstrates the impact of Fermi surface curvature on T_c and the non-monotonic gap structure in electron-doped cuprates, providing a theoretical explanation consistent with experiments.

Findings

Normal state exhibits non-Fermi liquid frequency dependencies

T_c approximately 10K, matching experimental data

Gap (k,) is strongly non-monotonic along the Fermi surface

Abstract

We study the normal state and pairing instability in electron-doped cuprates near optimal doping. We show that the fermionic self-energy has a non-Fermi liquid form leading to peculiar frequency dependencies of the conductivity and the Raman response. We solve the pairing problem and demonstrate that T_c is determined by the curvature of the Fermi surface, and the pairing gap \Delta(k,\omega) is strongly non-monotonic along the Fermi surface. The normal state frequency dependencies, the value of T_c\sim10K and the k-dependence of the gap agree with the experiment.