Measuring Rényi entanglement entropy with high efficiency and precision in quantum Monte Carlo simulations

This paper introduces a nonequilibrium increment method for efficiently and precisely calculating Rényi entanglement entropy in quantum Monte Carlo (QMC) simulations. The method's effectiveness is demonstrated on several challenging (2+1)d quantum lattice models, including the Heisenberg antiferromagnet, a quantum critical point with O(3) conformal field theory (CFT), the toric code Z₂ topological ordered state, and the Kagome Z₂ quantum spin liquid model. The results accurately reveal CFT data from logarithmic corrections and extract quantum dimensions in topological order from finite-size scaling. This establishes a controlled and practical computational approach for determining universal properties in highly entangled quantum matter.

Jiarui Zhao, Bin-Bin Chen, Yan-Cheng Wang, Zheng Yan, Meng Cheng, Zi Yang Meng