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arXiv · 2401.11659

Dynamical invariant based shortcut to equilibration in open quantum systems

Mohamed Boubakour·Shimpei Endo·Thomás Fogarty·Thomas Busch
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Abstract

We propose using the dynamical invariant also known as the Lewis-Riesenfeld invariant, to speed-up the equilibration of a driven open quantum system. This allows us to reverse engineer the time-dependent master equation that describes the dynamics of the open quantum system and systematically derive a protocol that realizes a shortcut to equilibration. The method does not require additional constraints on the timescale of the dynamics beside the Born-Markov approximation and can be generically applied to boost single particle quantum engines significantly. We demonstrate it with the damped harmonic oscillator, and show that our protocol can achieve a high-fidelity control in shorter timescales than simple non-optimized protocols. We find that the system is heated during the dynamics to speed-up the equilibration, which can be considered as an analogue of the Mpemba effect in quantum control.

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Mohamed Boubakour, Shimpei Endo, Thomás Fogarty, Thomas Busch. 2024-01-22. Dynamical invariant based shortcut to equilibration in open quantum systems. https://doi.org/10.1088/2058-9565%2Fadbcce

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