Critical Behaviour of Structure Factors at a Quantum Phase Transition

TL;DR

This paper reviews the theoretical and numerical behavior of structure factors at quantum phase transitions, highlighting model-specific differences away from critical points.

Contribution

It compares theoretical predictions with exact and numerical results across multiple quantum models, emphasizing model-dependent behaviors.

Findings

At critical wavevector, results align with theoretical expectations.

Different models show varied behaviors away from critical wavevector.

Highlights the importance of model-specific analysis in quantum phase transitions.

Abstract

We review the theoretical behaviour of the total and one-particle structure factors at a quantum phase transition for temperature T=0. The predictions are compared with exact or numerical results for the transverse Ising model, the alternating Heisenberg chain, and the bilayer Heisenberg model. At the critical wavevector, the results are generally in accord with theoretical expectations. Away from the critical wavevector, however, different models display quite different behaviours for the one-particle residues and structure factors.