Concurrence and entanglement on a 16-site spin-1/2 pyrochlore cluster

TL;DR

This paper investigates the entanglement properties of a 16-site spin-1/2 pyrochlore cluster in the quantum spin ice regime, revealing how lattice distortions affect ground state entanglement.

Contribution

It provides exact solutions for the ground state of a pyrochlore spin model and analyzes how entanglement varies with model parameters and lattice distortions.

Findings

Ground state is a singlet within certain parameter regions.

Entanglement varies with ground state composition.

Lattice distortion can disentangle the ground state.

Abstract

We examine the entanglement of the ground state of a 16-site spin-1/2 pyrochlore cluster in the quantum spin ice regime via various calculations of ${\cal I}$-concurrence. Exact ground state solutions to a quantum spin Hamiltonian with four nearest-neighbour exchange parameters were obtained using exact diagonalization. We present results for the ground state ${\cal I}$-concurrence in a region within the parameter space of the model where the ground state is a singlet. We discuss variations in the ${\cal I}$-concurrence in the context of the composition of the ground state and we demonstrate how a lattice distortion disentangles the state.