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arXiv · 2212.11289

Variational quantum dynamics of two-dimensional rotor models

Matija Medvidović·Dries Sels
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Abstract

We present a numerical method to simulate the dynamics of continuous-variable quantum many-body systems. Our approach is based on custom neural-network many-body quantum states. We focus on dynamics of two-dimensional quantum rotors and simulate large experimentally relevant system sizes by representing a trial state in a continuous basis and using state-of-the-art sampling approaches based on Hamiltonian Monte Carlo. We demonstrate the method can access quantities like the return probability and vorticity oscillations after a quantum quench in two-dimensional systems of up to 64 (8 $\times$ 8) coupled rotors. Our approach can be used for accurate nonequilibrium simulations of continuous systems at previously unexplored system sizes and evolution times, bridging the gap between simulation and experiment.

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Matija Medvidović, Dries Sels. 2022-12-21. Variational quantum dynamics of two-dimensional rotor models. https://doi.org/10.1103/prxquantum.4.040302

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