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arXiv · 1602.06164

Irreversibility in a unitary finite-rate protocol: The concept of internal friction

Selcuk Cakmak·Ferdi Altintas·Ozgur E. Mustecaplioglu
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Abstract

The concept of internal friction, a fully quantum mechanical phenomena, is investigated in a simple, experimentally accessible quantum system in which a spin-1/2 is driven by a transverse magnetic field in a quantum adiabatic process. The irreversible production of the waste energy due to the quantum friction is quantitatively analyzed in a forward-backward unitary transform of the system Hamiltonian by using the quantum relative entropy between the actual density matrix obtained in a parametric transformation and the one in a reversible adiabatic process. Analyzing the role of total transformation time and the different pulse control schemes on the internal friction reveal the non-monotone character of the internal friction as a function of the total protocol time and the possibility for almost frictionless solutions in finite-time transformations.

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Selcuk Cakmak, Ferdi Altintas, Ozgur E. Mustecaplioglu. 2016-04-26. Irreversibility in a unitary finite-rate protocol: The concept of internal friction. https://doi.org/10.1088/0031-8949%2F91%2F7%2F075101

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