Anomalous quantum-critical scaling corrections in Two-dimensional antiferromagnets

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.We would like to thank Ning Su, Stefan Wessel, and Matthias Vojta for useful discussions. The work of N.M. and D.-X.Y. was supported by Grants No. NKRDPC-2017YFA0206203, No. NKRDPC-2018YFA0306001, No. NSFC-11574404, No. NSFC-11275279, No. NSFG-2015A030313176, and the Leading Talent Program of Guangdong Special Projects. H.S. was supported by the China Postdoctoral Science Foundation under Grants No. 2016M600034 and No. 2017T100031. W.G. was supported by NSFC under Grants No. 11775021 and No. 11734002. A.W.S was supported by the NSF under Grant No. DMR-1710170 and by a Simons Investigator Award. Some of the calculations were carried out on Boston University's Shared Computing Cluster. (Leading Talent Program of Guangdong Special Projects; 2016M600034 - China Postdoctoral Science Foundation; 2017T100031 - China Postdoctoral Science Foundation; 11775021 - NSFC; 11734002 - NSFC; DMR-1710170 - NSF; Simons Investigator Award; NKRDPC-2017YFA0206203; NKRDPC-2018YFA0306001; NSFC-11574404; NSFC-11275279; NSFG-2015A030313176)First author draft and Published version