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arXiv · 2011.07924

Time-Evolving Weiss Fields in the Stochastic Approach to Quantum Spins

S. E. Begg·A. G. Green·M. J. Bhaseen
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Abstract

We investigate non-equilibrium quantum spin systems via an exact mapping to stochastic differential equations. This description is invariant under a shift in the mean of the Gaussian noise. We show that one can extend the simulation time for real-time dynamics in one and two dimensions by a judicious choice of this shift. This can be updated dynamically in order to reduce the impact of stochastic fluctuations. We discuss the connection to drift gauges in the gauge-P literature.

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S. E. Begg, A. G. Green, M. J. Bhaseen. 2020-11-16. Time-Evolving Weiss Fields in the Stochastic Approach to Quantum Spins. https://doi.org/10.1103/physrevb.104.024408

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