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Disorder Induced Phase Transition in a Random Quantum Antiferromagnet

Anders W. Sandvik·Marco Vekic
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Abstract

A two-dimensional Heisenberg model with random antiferromagnetic nearest-neighbor exchange is studied using quantum Monte Carlo techniques. As the strength of the randomness is increased, the system undergoes a transition from an antiferromagnetically ordered ground state to a gapless disordered state. The finite-size scaling of the staggered structure factor and susceptibility is consistent with a dynamic exponent $z = 2$.

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Anders W. Sandvik, Marco Vekic. 1994-06-05. Disorder Induced Phase Transition in a Random Quantum Antiferromagnet. https://doi.org/10.1103/physrevlett.74.1226

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