Continuous quantum phase transition between two topologically distinct valence bond solid states associated with the same spin value

TL;DR

This paper introduces a one-dimensional spin-2 model with two distinct valence bond solid states, analyzing the quantum phase transition between them and revealing a critical conformal field theory with central charge 2.

Contribution

It presents a simple spin-2 Hamiltonian with exactly solvable limits and characterizes the quantum phase transition between topologically distinct states using entanglement scaling.

Findings

Identifies two topologically distinct valence bond solid states.

Determines the critical point has a conformal field theory with central charge 2.

Uses tensor network algorithms to study the phase diagram.

Abstract

We propose a simple one-dimensional spin-2 Hamiltonian, which exhibits two topologically distinct valence bond solid states in different exactly solvable limits. We then construct the phase diagram and study the quantum phase transition between these states using the infinite time evolving block decimation algorithms. From the scaling relation between the entanglement entropy and correlation length, we find that the central charge for the underlying critical conformal field theory is $c=2$.