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arXiv · 1812.08821

Shortcut to Equilibration of an Open Quantum System

Roie Dann·Ander Tobalina·Ronnie Kosloff
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Abstract

We present a procedure to accelerate the relaxation of an open quantum system towards its equilibrium state. The control protocol, termed Shortcut to Equilibration, is obtained by reverse-engineering the non-adiabatic master equation. This is a non-unitary control task aimed at rapidly changing the entropy of the system. Such a protocol serves as a shortcut to an abrupt change in the Hamiltonian, i.e., a quench. As an example, we study the thermalization of a particle in a harmonic well. We observe that for short protocols there is a three orders of magnitude improvement in accuracy.

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Roie Dann, Ander Tobalina, Ronnie Kosloff. 2018-12-20. Shortcut to Equilibration of an Open Quantum System. https://doi.org/10.1103/physrevlett.122.250402

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