Phase diagram of the Cairo pentagonal XXZ spin-1/2 magnet under a magnetic field

TL;DR

This paper maps the phase diagram of the Cairo pentagonal XXZ spin-1/2 magnet under magnetic fields, revealing unconventional magnetic and topological phases driven by frustration and quantum fluctuations.

Contribution

It introduces a comprehensive analysis of the Cairo lattice XXZ model, identifying novel phases like a 1/3-ferrimagnetic plateau and a 5/12-topological phase using advanced computational methods.

Findings

Identification of a 1/3-ferrimagnetic plateau stabilized by quantum fluctuations.

Discovery of a 5/12-topological phase induced by ice-rule constraints.

Observation of a ferrimagnetic superfluid and its thermal melting behavior.

Abstract

The phase diagram of the XXZ spin-1/2 magnet, equivalent to hard-core bosons, under a staggered magnetic field and on the Cairo pentagonal lattice is computed at zero and finite temperature by using a cluster mean field theory and a stochastic series expansion quantum Monte Carlo.The complex connectivity and the frustration lead to unconventional phases such as a 1/3-ferrimagnetic plateau stabilized by quantum fluctuations as well as a 5/12-topological phase induced by a local ice-rule constraint. We also report the presence of a ferrimagnetic superfluid and its thermal melting. Finally, we discuss the ferro- and antiferro- magnetic (hopping sign) cases.