Domain Wall Dynamics near a Quantum Critical Point

TL;DR

This paper investigates the behavior of domain walls in a one-dimensional quantum spin chain near a critical point, revealing stability and divergence in width as the critical point is approached.

Contribution

It provides numerical evidence of domain wall stability and characterizes the divergence of domain wall width near the quantum critical point.

Findings

Domain walls are dynamically stable in the Heisenberg-Ising model.

Domain wall width diverges as $( ext{Delta} - 1)^{-1/2}$ near the critical point.

The study enhances understanding of quantum critical dynamics in spin chains.

Abstract

We study the real-time domain-wall dynamics near a quantum critical point of the one-dimensional anisotropic ferromagnetic spin 1/2 chain. By numerical simulation, we find the domain wall is dynamically stable in the Heisenberg-Ising model. Near the quantum critical point, the width of the domain wall diverges as $(\Delta -1) ^{-1/2}$.