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arXiv · 1307.2267

Nature of the phases in the frustrated XY model on the honeycomb lattice

Juan Carrasquilla·Andrea Di Ciolo·Federico Becca·Victor Galitski·Marcos Rigol
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Abstract

We study the phase diagram of the frustrated XY model on the honeycomb lattice by using accurate correlated wave functions and variational Monte Carlo simulations. Our results suggest that a spin-liquid state is energetically favorable in the region of intermediate frustration, intervening between two magnetically ordered phases. The latter ones are represented by classically ordered states supplemented with a long-range Jastrow factor, which includes relevant correlations and dramatically improves the description provided by the purely classical solution of the model. The construction of the spin-liquid state is based on a decomposition of the underlying bosonic particles in terms of spin-1/2 fermions (partons), with a Gutzwiller projection enforcing no single occupancy, as well as a long-range Jastrow factor.

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Juan Carrasquilla, Andrea Di Ciolo, Federico Becca, Victor Galitski, Marcos Rigol. 2013-07-08. Nature of the phases in the frustrated XY model on the honeycomb lattice. https://doi.org/10.1103/physrevb.88.241109

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