Validity of Harris criterion for two-dimensional quantum spin systems with quenched disorder

التفاصيل البيبلوغرافية
العنوان: Validity of Harris criterion for two-dimensional quantum spin systems with quenched disorder
المؤلفون: Peng, Jhao-Hong, Huang, L. -W., Tan, D. -R., Jiang, F. -J.
المصدر: Phys. Rev. B 101, 174404 (2020)
سنة النشر: 2019
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Disordered Systems and Neural Networks, Condensed Matter - Strongly Correlated Electrons
الوصف: Inspired by the recent results regarding whether the Harris criterion is valid for quantum spin systems, we have simulated a two-dimensional spin-1/2 Heisenberg model on the square lattice with a specific kind of quenched disorder using the quantum Monte Carlo (QMC) calculations. In particular, the considered quenched disorder has a tunable parameter $0\le p \le 1$ which can be considered as a measure of randomness. Interestingly, when the magnitude of $p$ increases from 0 to 0.9, at the associated quantum phase transitions the numerical value of the correlation length exponent $\nu$ grows from a number compatible with the $O(3)$ result 0.7112(5) to a number slightly greater than 1. In other words, by varying $p$, $\nu$ can reach an outcome between 0.7112(5) and 1 (or greater). Furthermore, among the studied values of $p$, all the associated $\nu$ violate the Harris criterion except the one corresponding to $p=0.9$. Considering the form of the employed disorder here, the above described scenario should remain true for other randomness if it is based on the similar idea as the one used in this study. This is indeed confirmed by our preliminary results stemming from investigating another disorder distribution.
Comment: 8 pages, 8 figures, 7 tables
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevB.101.174404
URL الوصول: http://arxiv.org/abs/1910.12705
رقم الأكسشن: edsarx.1910.12705
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevB.101.174404