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Exotic vs. conventional scaling and universality in a disordered bilayer quantum Heisenberg antiferromagnet

Rastko Sknepnek·Thomas Vojta·Matthias Vojta
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Abstract

We present large-scale Monte-Carlo simulations of a two-dimensional (2d) bilayer quantum Heisenberg antiferromagnet with random dimer dilution. In contrast to the exotic scaling scenarios found in many other random quantum systems, the quantum phase transition in this system is characterized by a finite-disorder fixed point with power-law scaling. After accounting for strong corrections to scaling, characterized by a leading irrelevant exponent of ω= 0.48, we find universal, i.e., disorder-independent, critical exponents z=1.310(6) and ν=1.16(3). We discuss the consequences of these findings and suggest new experiments.

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Rastko Sknepnek, Thomas Vojta, Matthias Vojta. 2004-09-01. Exotic vs. conventional scaling and universality in a disordered bilayer quantum Heisenberg antiferromagnet. https://doi.org/10.1103/physrevlett.93.097201

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