Detecting phase boundaries of quantum spin-1/2 XXZ ladder via bipartite and multipartite entanglement transitions

TL;DR

This paper uses bipartite and multipartite entanglement measures to identify phase boundaries in the ground states of a quantum spin-1/2 XXZ ladder, revealing detailed phase diagram features efficiently.

Contribution

It introduces a comprehensive entanglement-based approach to map the phase diagram of the XXZ ladder, highlighting finer details beyond traditional methods.

Findings

Entanglement measures successfully identify known phase boundaries.

Ground state entanglement reveals finer phase diagram details.

Analysis is effective with moderate system sizes.

Abstract

Phase transition in quantum many-body systems inevitably causes changes in certain physical properties which then serve as potential indicators of critical phenomena. Besides the traditional order parameters, characterization of quantum entanglement has proven to be a computationally efficient and successful method for detection of phase boundaries, especially in one-dimensional models. Here we determine the rich phase diagram of the ground states of a quantum spin-1/2 XXZ ladder by analyzing the variation of bipartite and multipartite entanglements. Our study characterizes the different ground state phases and notes the correspondence with known results, while highlighting the finer details that emerge from the behavior of ground state entanglement. Analysis of entanglement in the ground state provides a clearer picture of the complex ground state phase diagram of the system using only a moderate-size model.