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arXiv · 2311.17622

Non-Markovianity Benefits Quantum Dynamics Simulation

Abstract

Quantum dynamics simulation on analog quantum simulators and digital quantum computer platforms has emerged as a powerful and promising tool for understanding complex non-equilibrium physics. However, the impact of quantum noise on the dynamics simulation, particularly non- Markovian noise with memory effects, has remained elusive. In this Letter, we discover unexpected benefits of non-Markovianity of quantum noise in quantum dynamics simulation. We demonstrate that non-Markovian noise with memory effects and temporal correlations can significantly improve the accuracy of quantum dynamics simulation compared to the Markovian noise of the same strength. Through analytical analysis and extensive numerical experiments, we showcase the positive effects of non-Markovian noise in various dynamics simulation scenarios, including decoherence dynamics of idle qubits, intriguing non-equilibrium dynamics observed in symmetry protected topological phases, and many-body localization phases. Our findings shed light on the importance of considering non- Markovianity in quantum dynamics simulation, and open up new avenues for investigating quantum phenomena and designing more efficient quantum technologies.

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Yu-Qin Chen, Shi-Xin Zhang, Shengyu Zhang. 2023-11-29. Non-Markovianity Benefits Quantum Dynamics Simulation. https://doi.org/10.1002/qute.202500405

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