Three-dimensional unfrustrated and frustrated quantum Heisenberg magnets. Specific heat study

TL;DR

This study investigates how different three-dimensional lattice geometries influence the finite-temperature thermodynamic properties, especially specific heat, of $S=1/2$ Heisenberg magnets with ferromagnetic and antiferromagnetic interactions using advanced computational methods.

Contribution

It provides a comparative analysis of specific heat behavior across four 3D lattices for both signs of exchange interactions, highlighting the impact of lattice geometry on thermodynamics.

Findings

Lattice geometry significantly affects specific heat profiles.

Frustrated lattices show distinct thermodynamic signatures.

Results offer insights into hidden energy scales in frustrated magnets.

Abstract

We examine the $S=1/2$ Heisenberg magnet on four three-dimensional lattices - simple-cubic, diamond, pyrochlore, and hyperkagome ones - for ferromagnetic and antiferromagnetic signs of the exchange interaction in order to illustrate the effect of lattice geometry on the finite-temperature thermodynamic properties with a focus on the specific heat $c(T)$. To this end, we use quantum Monte Carlo simulations or high-temperature expansion series complemented with the entropy method. We also discuss a recent proposal about hidden energy scale in geometrically frustrated magnets.