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arXiv · 0707.2961

Scaling in the Fan of an Unconventional Quantum Critical Point

Roger G. Melko·Ribhu K. Kaul
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Abstract

We present results of extensive finite-temperature Quantum Monte Carlo simulations on a SU(2) symmetric S=1/2 quantum antiferromagnet with a four-spin interaction [Sandvik, Phys. Rev. Lett. 98, 227202 (2007)]. Our simulations, which are free of the sign-problem and carried out on lattices containing in excess of 1.6 X 10^4 spins, indicate that the four-spin interaction destroys the Néel order at an unconventional z=1 quantum critical point, producing a valence-bond solid paramagnet. Our results are consistent with the `deconfined quantum criticality' scenario.

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Roger G. Melko, Ribhu K. Kaul. 2008-01-09. Scaling in the Fan of an Unconventional Quantum Critical Point. https://doi.org/10.1103/physrevlett.100.017203

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