Universal Finite Temperature Properties of a Three Dimensional Quantum Antiferromagnet in the Vicinity of a Quantum Critical Point

TL;DR

This paper investigates the universal finite-temperature properties of a 3D quantum antiferromagnet near a quantum critical point, combining field theory and numerical simulations to reveal universal behavior and compare with experimental data.

Contribution

It demonstrates the universal behavior of a 3D quantum antiferromagnet near a QCP using a combination of quantum field theory and numerical modeling.

Findings

Néel temperature approaches zero near QCP

Universal behavior observed near the quantum critical point

Comparison with experimental data for TlCuCl₃ supports theoretical predictions

Abstract

We consider a 3-dimensional quantum antiferromagnet which can be driven through a quantum critical point (QCP) by varying a tuning parameter g. Starting from the magnetically ordered phase, the N{\'e}el temperature will decrease to zero as the QCP is approached. From a generic quantum field theory, together with numerical results from a specific microscopic Heisenberg spin model, we demonstrate the existence of universal behaviour near the QCP. We compare our results with available data for TlCuCl_3