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arXiv · 1105.5671

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

Arnaud Ralko
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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.

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Arnaud Ralko. 2011-05-27. Phase diagram of the Cairo pentagonal XXZ spin-1/2 magnet under a magnetic field. https://doi.org/10.1103/physrevb.84.184434

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