A spin-dependent local moment approach to the Anderson impurity model

TL;DR

This paper extends the local moment approach to the Anderson impurity model with spin-dependent hybridization, applying symmetry restoration and variational methods, and validates results against numerical renormalization group calculations.

Contribution

It introduces a spin-dependent local moment approach with symmetry restoration for the Anderson model, enhancing analysis of quantum dots with ferromagnetic leads.

Findings

Results agree with numerical renormalization group calculations.

The approach effectively models spin-dependent hybridization effects.

Ground states are determined through variational energy minimization.

Abstract

We present an extension of the local moment approach to the Anderson impurity model with spin-dependent hybridization. By employing the two-self-energy description, as originally proposed by Logan and co-workers, we applied the symmetry restoration condition for the case with spin-dependent hybridization. Self-consistent ground states were determined through variational minimization of the ground state energy. The results obtained with our spin-dependent local moment approach applied to a quantum dot system coupled to ferromagnetic leads are in good agreement with those obtained from previous work using numerical renormalization group calculations.