Entanglement entropy, fidelity and the phase transition of one-dimensional hard-core bosonic system with three-body interactions

TL;DR

This paper investigates phase transitions in a one-dimensional hard-core bosonic system with three-body interactions, revealing an intermediate phase between charge-density wave and superfluid phases using entanglement entropy and fidelity analysis.

Contribution

It introduces the use of entanglement entropy and fidelity susceptibility to detect and characterize phase transitions, including a novel intermediate phase, in a 1D hard-core bosonic system with three-body interactions.

Findings

Identification of superfluid phase transition point via entanglement entropy

Discovery of an intermediate phase between CDW and superfluid phases

Entanglement entropy behavior indicating melting of CDW phase

Abstract

We study the one-dimensional hard-core Bose-Hubbard model with three-body interactions. In previous work[1], the two-thirds filling solid with both bond-wave order (BOW) and charge-density wave order (CDW) is found and it undergoes a second order phase transition to the superfluid phase. However, in recent work[2], we found the BOW not independent with CDW order. Thus, by utilizing the density matrix renormalization group, we make use of both entanglement entropy and fidelity susceptibility to detect the phase transition. In two-thirds filling, the extreme point of the entanglement entropy also indicates the superfluid phase transition point. However, the pairwise entanglement entropy drop quickly after additional critical point, such disentangled behaviour demonstrates another melting point to the CDW phase. Thus, a novel intermediate phase between CDW phase and superfluid phase is found. At last, we analyzed the half filling case with entanglement entropy.