Energy transfer using unitary transformations

Winny O'Kelly de Galway; Jan Naudts

doi:10.3390/e15125121

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arXiv · 1307.0381

Energy transfer using unitary transformations

Winny O'Kelly de Galway·Jan Naudts

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Abstract

We study the unitary time evolution of a simple quantum Hamiltonian describing two harmonic oscillators coupled via a three-level system. The latter acts as an engine transferring energy from one oscillator to the other and is driven in a cyclic manner by time-dependent external fields. The S-matrix of the cycle is obtained in analytic form. The total number of quanta contained in the system is a conserved quantity. As a consequence the spectrum of the S-matrix is purely discrete and the evolution of the system is quasi-periodic.

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Winny O'Kelly de Galway, Jan Naudts. 2013-06-24. Energy transfer using unitary transformations. https://doi.org/10.3390/e15125121

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