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arXiv · 1403.4497

One-dimensional spin liquid, collinear, and spiral phases from uncoupled chains to the triangular lattice

Luca F. Tocchio·Claudius Gros·Roser Valentí·Federico Becca
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Abstract

We investigate the Hubbard model on the anisotropic triangular lattice with two hopping parameters $t$ and $t^\prime$ in different spatial directions, interpolating between decoupled chains ($t=0$) and the isotropic triangular lattice ($t=t^\prime$). Variational wave functions that include both Jastrow and backflow terms are used to compare spin-liquid and magnetic phases with different pitch vectors describing both collinear and coplanar (spiral) order. For relatively large values of the on-site interaction $U/t^\prime \gtrsim 10$ and substantial frustration, i.e., $0.3\lesssim t/t^\prime \lesssim 0.8$, the spin-liquid state is clearly favored over magnetic states. Spiral magnetic order is only stable in the vicinity of the isotropic point, while collinear order is obtained in a wide range of inter-chain hoppings from small to intermediate frustration.

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Luca F. Tocchio, Claudius Gros, Roser Valentí, Federico Becca. 2014-03-18. One-dimensional spin liquid, collinear, and spiral phases from uncoupled chains to the triangular lattice. https://doi.org/10.1103/physrevb.89.235107

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