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Classical Correlation-Length Exponent in Non-Universal Quantum Phase Transition of Diluted Heisenberg Antiferromagnet

C. Yasuda·S. Todo·K. Harada·N. Kawashima·S. Miyashita·H. Takayama
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Abstract

Critical behavior of the quantum phase transition of a site-diluted Heisenberg antiferromagnet on a square lattice is investigated by means of the quantum Monte Carlo simulation with the continuous-imaginary-time loop algorithm. Although the staggered spin correlation function decays in a power law with the exponent definitely depending on the spin size $S$, the correlation-length exponent is classical, i.e., $ν=4/3$. This implies that the length scale characterizing the non-universal quantum phase transition is nothing but the mean size of connected spin clusters.

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C. Yasuda, S. Todo, K. Harada, N. Kawashima, S. Miyashita, H. Takayama. 2000-10-25. Classical Correlation-Length Exponent in Non-Universal Quantum Phase Transition of Diluted Heisenberg Antiferromagnet. https://doi.org/10.1103/physrevb.63.140415

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