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XY ring-exchange model on the triangular lattice

Leon Balents·Arun Paramekanti
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Abstract

We study ring-exchange models for bosons or XY-spins on the triangular lattice. A four-spin exchange leads to a manifold of ground states with gapless excitations and critical power-law correlations. With a nearest-neighbour exchange, fluctuations select a four-fold ferrimagnetically ordered ground state with a small spin/superfluid stiffness which breaks the global U(1) and translational symmetry. We explore consequences for phase transitions at finite temperature and in an in-plane magnetic field.

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Leon Balents, Arun Paramekanti. 2003-01-14. XY ring-exchange model on the triangular lattice. https://doi.org/10.1103/physrevb.67.134427

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