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arXiv · 2503.11577

Bosonized one-dimensional quantum systems through enhanced event-chain Monte Carlo

Oscar Bouverot-Dupuis·Alberto Rosso·Manon Michel
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Abstract

We design an enhanced Event-Chain Monte Carlo algorithm to study 1D quantum dissipative systems, using their bosonized representation. Expressing the bosonized Hamiltonian as a path integral over a scalar field enables the application of Monte Carlo algorithms developed for classical systems. Specifically, we focus on a dissipative XXZ spin chain, exhibiting critical slowing down, minima degeneracy and long-range interactions. Addressing all three bottlenecks, we design an algorithm that combines local persistent Event-Chain Monte Carlo moves with global cluster moves, in a O(1)-complexity implementation. Through systematic performance analysis, we show that such an algorithm outperforms traditional Metropolis algorithms by more than a magnitude factor and is competitive with current state-of-the-art Quantum Monte Carlo algorithms. We then use this approach to determine the dissipative spin chain's phase diagram, thereby reinforcing prior analytical predictions.

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Oscar Bouverot-Dupuis, Alberto Rosso, Manon Michel. 2025-03-14. Bosonized one-dimensional quantum systems through enhanced event-chain Monte Carlo. https://doi.org/10.1103/k43n-yz82

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