Pseudogap Formation in the Symmetric Anderson Lattice Model

TL;DR

This paper investigates pseudogap formation in the symmetric Anderson lattice model using self-consistent calculations, revealing temperature-dependent spectral and magnetic properties relevant to strongly correlated electron systems.

Contribution

It provides a detailed analysis of pseudogap emergence in the Anderson lattice model through fluctuation exchange approximation, highlighting temperature effects on spectral functions and susceptibilities.

Findings

Pseudogap forms at a characteristic temperature T_x.

Spectral functions narrow as temperature decreases.

Pseudogap approximately equals the hybridization gap at low T.

Abstract

We present self-consistent calculations for the self-energy and magnetic susceptibility of the 2D and 3D symmetric Anderson lattice Hamiltonian, in the fluctuation exchange approximation. At high temperatures, strong f-electron scattering leads to broad quasiparticle spectral functions, a reduced quasiparticle band gap, and a metallic density of states. As the temperature is lowered, the spectral functions narrow and a pseudogap forms at the characteristic temperature $T_x$ at which the width of the quasiparticle spectral function at the gap edge is comparable to the renormalized activation energy. For $T << T_x $, the pseudogap is approximately equal to the hybridization gap in the bare band structure. The opening of the pseudogap is clearly apparent in both the spin susceptibility and the compressibility.