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arXiv · 1912.03313

Entanglement Renyi negativity across a finite temperature transition: a Monte Carlo study

Kai-Hsin Wu·Tsung-Cheng Lu·Chia-Min Chung·Ying-Jer Kao·Tarun Grover
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Abstract

Quantum entanglement is fragile to thermal fluctuations, which raises the question whether finite temperature phase transitions support long-range entanglement similar to their zero temperature counterparts. Here we use quantum Monte Carlo simulations to study the third Renyi negativity, a generalization of entanglement negativity, as a proxy of mixed-state entanglement in the 2D transverse field Ising model across its finite temperature phase transition. We find that the area-law coefficient of the Renyi negativity is singular across the transition, while its subleading constant is zero within the statistical error. This indicates that the entanglement is short-ranged at the critical point despite a divergent correlation length. Renyi negativity in several exactly solvable models also shows qualitative similarities to that in the 2D transverse field Ising model.

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Kai-Hsin Wu, Tsung-Cheng Lu, Chia-Min Chung, Ying-Jer Kao, Tarun Grover. 2019-12-06. Entanglement Renyi negativity across a finite temperature transition: a Monte Carlo study. https://doi.org/10.1103/physrevlett.125.140603

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