Continuous measurements on continuous variable quantum systems: The Gaussian description
Abstract
The Gaussian state description of continuous variables is adapted to describe the quantum interaction between macroscopic atomic samples and continuous-wave light beams. The formalism is very efficient: a non-linear differential equation for the covariance matrix of the atomic system explicitly accounts for both the unitary evolution, the dissipation and noise due to the atom-light interaction, and the back-action due to homodyne optical detection on the beam after its interaction with the atoms. Applications to atomic spin squeezing and estimation of unknown classical parameters are presented, and extensions beyond the Gaussian states are discussed.
Cite
@article{arxiv.quant-ph/0511154,
title = {Continuous measurements on continuous variable quantum systems: The Gaussian description},
author = {L. B. Madsen and K. Mølmer},
journal= {arXiv preprint arXiv:quant-ph/0511154},
year = {2007}
}
Comments
15 pages, 4 figures. Modified version of a contribution to the book "Quantum Information with Continuous Variables", Eds. G. Leuchs, N. Cerf, and E. Polzik. To be published by Imperial College Press