Anomalous quantum-critical scaling corrections in Two-dimensional antiferromagnets

Files
1804.01273v1.pdf(253.67 KB)
First author draft
PhysRevLett.121.117202.pdf(314.77 KB)
Published version
Date
2018-09-12
Authors
Ma, Nvsen
Weinberg, Phillip
Shao, Hui
Guo, Wenan
Yao, Dao-Xin
Sandvik, Anders W.
Version
First author draft and Published versions
OA Version
Citation
Nvsen Ma, Phillip Weinberg, Hui Shao, Wenan Guo, Dao-Xin Yao, Anders W Sandvik. 2018. "Anomalous Quantum-Critical Scaling Corrections in Two-Dimensional Antiferromagnets." Phys. Rev. Lett. 121, 117202. https://doi.org/10.1103/PhysRevLett.121.117202
Abstract
We study the Néel-paramagnetic quantum phase transition in two-dimensional dimerized S = 1 / 2 Heisenberg antiferromagnets using finite-size scaling of quantum Monte Carlo data. We resolve the long-standing issue of the role of cubic interactions arising in the bond-operator representation when the dimer pattern lacks a certain symmetry. We find nonmonotonic (monotonic) size dependence in the staggered (columnar) dimerized model, where cubic interactions are (are not) present. We conclude that there is a new irrelevant field in the staggered model, but, at variance with previous claims, it is not the leading irrelevant field. The new exponent is ω 2 ≈ 1.25 and the prefactor of the correction L − ω 2 is large and comes with a different sign from that of the conventional correction with ω 1 ≈ 0.78. Our study highlights competing scaling corrections at quantum critical points.
Description
License
© 2018 American Physical Society