Confined gap excitation and multielectron localization in magnetic alloys

TL;DR

This paper investigates a modified Anderson model revealing hidden integrability, leading to the discovery of confined gap excitations, heavy bound complexes, and multielectron localized states in magnetic alloys.

Contribution

It introduces a nonlinear dispersion and energy-dependent hybridization in the Anderson model, demonstrating hidden integrability and new localized phenomena.

Findings

Presence of confined gap excitations

Heavy bound complexes near the impurity

Multielectron localized states predicted

Abstract

The degenerate Anderson model with a nonlinear electron dispersion and an energy dependent hybridization is proven to exhibit hidden integrability and is diagonalized by the Bethe ansatz. If the impurity $f$-level energy lies below the conduction band edge, the spectrum of the system is shown to contain pairs of confined ``gap excitations'' and their heavy bound complexes. In addition, multielectron localized states due to a pinning of gap bound complexes to the impurity are predicted.