Next Article in Journal
The κ-Generalizations of Stirling Approximation and Multinominal Coefficients
Previous Article in Journal
Co-Evolutionary Mechanisms of Emotional Bursts in Online Social Dynamics and Networks
Article Menu

Export Article

Open AccessArticle
Entropy 2013, 15(12), 5121-5143; doi:10.3390/e15125121

Energy Transfer Using Unitary Transformations

1
Institute for Theoretical Physics, KU Leuven, Leuven B-3001, Belgium
2
Physics Department, University of Antwerp, Universiteitsplein 1, Antwerpen B-2610, Belgium
*
Author to whom correspondence should be addressed.
Received: 16 July 2013 / Revised: 22 October 2013 / Accepted: 18 November 2013 / Published: 26 November 2013
View Full-Text   |   Download PDF [268 KB, uploaded 24 February 2015]   |  

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 (scattering 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. The explicit knowledge of the S-matrix makes it possible to do accurate numerical evaluations of the time-dependent wave function. They confirm the quasi-periodic behavior. In particular, the energy flows back and forth between the two oscillators in a quasi-periodic manner. View Full-Text
Keywords: quantum stirring; S-matrix; driven quantum system; three-level system quantum stirring; S-matrix; driven quantum system; three-level system
This is an open access article distributed under the Creative Commons Attribution License (CC BY 3.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

de Galway, W.O.; Naudts, J. Energy Transfer Using Unitary Transformations. Entropy 2013, 15, 5121-5143.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Entropy EISSN 1099-4300 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top