Compass model on a ladder and square clusters

TL;DR

This paper calculates exact heat capacities of the quantum compass model on small square clusters and a ladder, revealing differences from the classical model through intersite correlations.

Contribution

It provides exact heat capacity calculations for quantum compass models on small clusters and compares them with ladder systems, highlighting quantum effects.

Findings

Quantum compass model differs from classical version in intersite correlations.

Exact heat capacities obtained for small clusters using Kernel Polynomial Method.

Differences observed between square clusters and ladder systems.

Abstract

We obtained exact heat capacities of the quantum compass model on the square L x L clusters with L=2,3,4,5 using Kernel Polynomial Method and compare them with heat capacity of a large compass ladder. Intersite correlations found in the ground state for these systems demonstrate that the quantum compass model differs from its classical version.