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arXiv · 1405.7882

Real-Time Simulation of Large Open Quantum Spin Systems driven by Measurements

D. Banerjee·F. -J. Jiang·M. Kon·U. -J. Wiese
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Abstract

We consider a large quantum system with spins $\frac{1}{2}$ whose dynamics is driven entirely by measurements of the total spin of spin pairs. This gives rise to a dissipative coupling to the environment. When one averages over the measurement results, the corresponding real-time path integral does not suffer from a sign problem. Using an efficient cluster algorithm, we study the real-time evolution of a 2-d Heisenberg antiferromagnet, which is driven to a disordered phase, either by sporadic measurements or by continuous monitoring described by Lindblad evolution.

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D. Banerjee, F. -J. Jiang, M. Kon, U. -J. Wiese. 2014-05-30. Real-Time Simulation of Large Open Quantum Spin Systems driven by Measurements. https://doi.org/10.1103/physrevb.90.241104

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