Distinguishing Phases with Ansatz Wavefunctions

TL;DR

This paper introduces a new measure to compare ansatz wavefunctions with numerical solutions, enabling phase distinction and critical point identification in quantum systems.

Contribution

It presents an efficient correlation-based indistinguishability measure for ansatz wavefunctions, applicable to phase classification and quantum critical point detection.

Findings

Successfully applied to the transverse Ising model

Distinguishes phases via correlator classes

Identifies quantum critical points

Abstract

We propose an indistinguishability measure for assessment of ansatz wavefunctions with numerically determined wavefunctions. The measure efficiently compares all correlation functions of two states and can therefore be used to distinguish phases by defining correlator classes for ansatz wavefunctions. It also allows identification of quantum critical points. We demonstrate the approach for the transverse Ising model, using the matrix product state formalism with the time evolving block decimation algorithm.