Photon storage in Lambda-type optically dense atomic media. IV. Optimal control using gradient ascent
Abstract
We use the numerical gradient ascent method from optimal control theory to extend efficient photon storage in Lambda-type media to previously inaccessible regimes and to provide simple intuitive explanations for our optimization techniques. In particular, by using gradient ascent to shape classical control pulses used to mediate photon storage, we open up the possibility of high efficiency photon storage in the non-adiabatic limit, in which analytical solutions to the equations of motion do not exist. This control shaping technique enables an order-of-magnitude increase in the bandwidth of the memory. We also demonstrate that the often discussed connection between time reversal and optimality in photon storage follows naturally from gradient ascent. Finally, we discuss the optimization of controlled reversible inhomogeneous broadening.
Cite
@article{arxiv.0710.2698,
title = {Photon storage in Lambda-type optically dense atomic media. IV. Optimal control using gradient ascent},
author = {Alexey V. Gorshkov and Tommaso Calarco and Mikhail D. Lukin and Anders S. Sorensen},
journal= {arXiv preprint arXiv:0710.2698},
year = {2008}
}
Comments
16 pages, 7 figures. V2: As published in Phys. Rev. A. Moved most of the math to appendices or removed altogether. Switched order of Sections II and III. Shortened abstract. Added references