Controlling spontaneous-emission noise in measurement-based feedback cooling of a Bose-Einstein Condensate
Abstract
Off-resonant optical imaging is the most popular method for continuous monitoring of a Bose-Einstein condensate (BEC). However, the disturbance caused by scattered photons places a serious limitation on the lifetime of such continuously-monitored condensates. In this paper, we demonstrate that a new choice of feedback control can overcome the heating effects of the measurement backaction. In particular, we show that the measurement backaction caused by off-resonant optical imaging is a multimode quantum-field effect, as the entire heating process is not seen in single-particle or mean-field models of the system. Correctly simulating such continuously-monitored systems is only possible using the number-phase Wigner (NPW) particle filter, which is a hybrid between the leading techniques for simulating non-equilibrium dynamics in condensates and particle filters for simulating high-dimensional non-Gaussian filters in the field of engineering. The new control scheme will enable long-term continuous measurement and feedback on one of the leading platforms for precision measurement and the simulation of quantum fields, allowing for the possibility of single-shot experiments, adaptive measurements and robust state-preparation and manipulation.
Keywords
Cite
@article{arxiv.1301.1963,
title = {Controlling spontaneous-emission noise in measurement-based feedback cooling of a Bose-Einstein Condensate},
author = {M. R. Hush and S. S. Szigeti and A. R. R. Carvalho and J. J. Hope},
journal= {arXiv preprint arXiv:1301.1963},
year = {2015}
}
Comments
19 pages, 4 figures