Superconductivity in the Anderson Lattice

TL;DR

This paper investigates superconductivity in the Anderson lattice with anisotropic hybridization, revealing new pairing instabilities due to density fluctuation exchange, differing from previous spherical symmetry models.

Contribution

It introduces an anisotropic hybridization model and demonstrates its impact on quasiparticle interactions and pairing instabilities in the Anderson lattice.

Findings

Identifies E$_g$ and T$_{1g}$ pairing instabilities

Finds significant differences from spherical symmetry models

Highlights the role of density fluctuations in pairing

Abstract

Using an anisotropic hybridization matrix element, V($\vec k$), reflecting cubic symmetry at the ``rare-earth'' sites of the infinite U Anderson lattice, we calculate the bare quasiparticle scattering amplitude to order 1/N using slave Bosons and find significant differences with previous results under spherical symmetry. Due to exchange of density fluctuations, we find an instability. toward E$_g$ and T$_{1g}$ (even-parity) pairing.