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arXiv · 1411.4649

Quantum paramagnet in a $π$ flux triangular lattice Hubbard model

Stephan Rachel·Manuel Laubach·Johannes Reuther·Ronny Thomale
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Abstract

We propose the $π$ flux triangular lattice Hubbard model ($π$-THM) as a prototypical setup to stabilize magnetically disordered quantum states of matter in the presence of charge fluctuations. The quantum paramagnetic domain of the $π$-THM which we identify for intermediate Hubbard U is framed by a Dirac semi-metal for weak coupling and by 120${}^{\circ}$ Néel order for strong coupling. Generalizing the Klein duality from spin Hamiltonians to tight-binding models, the $π$-THM maps to a Hubbard model which corresponds to the $(J_H, J_K)=(-1,2)$ Heisenberg-Kitaev model in its strong coupling limit. The $π$-THM provides a promising microscopic testing ground for exotic finite-U spin liquid ground states amenable to numerical investigation.

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Stephan Rachel, Manuel Laubach, Johannes Reuther, Ronny Thomale. 2015-04-07. Quantum paramagnet in a $π$ flux triangular lattice Hubbard model. https://doi.org/10.1103/physrevlett.114.167201

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