Dissipative dynamics of an extended magnetic nanostructure: Spin necklace in a metallic environment

TL;DR

This paper investigates the dissipative quantum dynamics of a spin necklace coupled to conduction electrons, revealing size-dependent effects and employing a Coulomb gas mapping and numerical analysis.

Contribution

It introduces a theoretical framework for analyzing the long-time behavior of a spin necklace in a metallic environment, highlighting size-dependent quantum fluctuations.

Findings

Couplings depend nontrivially on system size due to quantum fluctuations.

Mapping to a multichannel Coulomb gas enables analysis of dissipative dynamics.

Numerical evaluation confirms the analytical predictions.

Abstract

We study theoretically the dynamics of an ``xxz'' spin necklace coupled to a conduction electron sea, a model system for a nanostructure in a dissipative environment. We extract the long-time behavior via a mapping to a multichannel Coulomb gas problem followed by a scaling analysis. The strong quantum fluctuations of the necklace cause a nontrivial dependence of couplings on system size which we extract via an analysis involving the ``boundary condition changing operator'', and confirm via a detailed numerical evaluation of one case.