Interaction effects between impurities in low dimensional spin-1/2 antiferromagnets

TL;DR

This paper investigates how multiple non-magnetic impurities interact within low-dimensional spin-1/2 antiferromagnetic systems, revealing insights into quantum correlations and valence bond ground states through numerical simulations.

Contribution

It provides a detailed numerical analysis of impurity interactions in various low-dimensional antiferromagnets, highlighting the role of quantum correlations and valence bonds.

Findings

Large effective interactions indicate strong quantum correlations.

Interactions vary between 1D, ladders, and 2D systems.

Valence bond states influence impurity interactions.

Abstract

We are considering the interplay between several non-magnetic impurities in the spin-1/2 Heisenberg antiferromagnet in chains, ladders and planes by introducing static vacancies in numerical quantum Monte Carlo simulations. The effective potential between two and more impurities is accurately determined, which gives a direct measure of the quantum correlations in the systems. Large effective interaction potentials are an indication of strong quantum correlations in the system and reflect the detailed nature of the valence bond ground states. In two-dimensions (2D) the interactions are smaller, but can still be analyzed in terms of valence bonds.