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arXiv · 0907.4163

Phase diagram of the spin-1/2 $J_1$-$J_2$-$J_3$ Heisenberg model on the square lattice

Philippe Sindzingre·Nic Shannon·Tsutomu Momoi
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Abstract

We presents the results of an extensive numerical study of the phase diagram of the spin-1/2, \protect{$J_1$-$J_2$-$J_3$} Heisenberg model on a square lattice, for both ferromagnetic and antiferromagnetic nearest-neighbor interactions $J_1$, using exact diagonalization with periodic and twisted boundary conditions. Comparison is made with published spin wave calculations. We show that quantum fluctuations play a very important role, changing both the extent and the wave vector of classical spiral phases, and leading to new quantum phases where the classical spiral states have a high degeneracy. These include a new phase with small or vanishing spin-stiffness, in addition to known valence-bond-solid and bond-nematic phases.

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Philippe Sindzingre, Nic Shannon, Tsutomu Momoi. 2009-07-23. Phase diagram of the spin-1/2 $J_1$-$J_2$-$J_3$ Heisenberg model on the square lattice. https://doi.org/10.1088/1742-6596/200/2/022058

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