Protecting Schrodinger Cat States By Use Of Feedback

David Vitali, P. Tombesi, Gerard J Milburn

José Manuel Morgado Chávez, Philip D. Mauskopf

David Vitali, P. Tombesi, Gerard J Milburn

A feedback model based on direct photodetection and micromaser-like atomic injection is proposed for the preservation of quantum coherence in a cavity. We show that in this way it is possible to slow down significantly the decoherence of Schrödinger cat states.

Peter Goetsch, Paolo Tombesi, David Vitali

The linear stochastic Schr\"odinger equation of a cavity mode subject to a homodyne measurement and to a phase-sensitive feedback loop realized with part of the output homodyne photocurrent is derived. We show that quantum feedback has stabilizing effects which manifest themselves in a significant retardation of the decoherence of a Schr\"odinger-cat state. \textcopyright{} 1996 The American Physical Society.

Justin Finn, Kurt A. Jacobs

David Vitali, P. Tombesi, Gerard J Milburn

We propose a simple modification of the experimental scheme employed by Brune et al. [Phys. Rev. Lett. 77, 4887 (1996)] for the generation and detection of a Schr\"odinger cat state, in which the decoherence of the cat state can be significantly slowed down using an appropriate feedback.