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arXiv · 1403.1406

Baxter-Wu model in a transverse magnetic field

Sylvain Capponi·Saeed S. Jahromi·Fabien Alet·Kai Phillip Schmidt
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Abstract

We investigate the low-energy properties as well as quantum and thermal phase transitions of the Baxter-Wu model in a transverse magnetic field. Our study relies on stochastic series expansion quantum Monte Carlo and on series expansions about the low- and high-field limits at zero temperature using the quantum finite-lattice method on the triangular lattice. The phase boundary consists of a second-order critical line in the 4-state Potts model universality class starting from the pure Baxter-Wu limit meeting a first-order line connected to the zero-temperature transition point ($h\approx2.4$, $T=0$). Both lines merge at a tricritical point approximatively located at ($h\approx 2.3J$, $T\approx J$).

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Sylvain Capponi, Saeed S. Jahromi, Fabien Alet, Kai Phillip Schmidt. 2014-07-08. Baxter-Wu model in a transverse magnetic field. https://doi.org/10.1103/physreve.89.062136

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