Excitation Spectrum at the Yang-Lee Edge Singularity of 2D Ising Model on the Strip

TL;DR

This paper investigates the excitation spectrum at the Yang-Lee edge singularity of the 2D Ising model on a strip, using finite-size scaling to identify the underlying conformal field theory.

Contribution

It provides the first measurement of the low-lying excitation spectrum at the Yang-Lee edge singularity for free boundary conditions in the 2D Ising model.

Findings

Spectrum matches predictions from conformal field theory

Identifies the specific CFT describing the edge singularity

Demonstrates finite-size scaling effectiveness

Abstract

At the Yang-Lee edge singularity, finite-size scaling behavior is used to measure the low-lying excitation spectrum of the Ising quantum spin chain for free boundary conditions. The measured spectrum is used to identify the CFT that describes the Yang-Lee edge singularity of the 2D Ising model for free boundary conditions.