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arXiv · 2408.12507

Stochastically bundled dissipators for the quantum master equation

Sayak Adhikari·Roi Baer
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Abstract

The Lindblad master equation is a fundamental tool for describing the evolution of open quantum systems, but its computational complexity poses a significant challenge, especially for large systems. This article introduces a stochastic representation of the Lindblad dissipator that addresses this challenge by bundling the Lindblad operators. We demonstrate the effectiveness of this method by considering a Morse oscillator coupled to a spin bath. Our numerical experiments show that a small number of stochastically bundled operators can accurately capture the system's dynamics, even when the Hilbert space dimension is large. This method offers a new perspective on open quantum systems and provides a computationally efficient way to simulate their dynamics.

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Sayak Adhikari, Roi Baer. 2024-08-22. Stochastically bundled dissipators for the quantum master equation. https://doi.org/10.1021/acs.jctc.5c00145

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