Fluctuations in quantum optical systems : from Bose-Einstein condensates to squeezed states of light

Vitaly V. Kocharovsky, Vl. V. Kocharovsky, Martin Holthaus +4 more

Aranya B. Bhattacherjee

We study an optomechanical system in which the collective density excitations (Bogoliubov modes) of a Bose Einstein condensate (BEC) is coupled to a cavity field. We show that the optical force changes the frequency and the damping constant of the collective density excitations of the BEC. We further analyze the occurrence of normal mode splitting (NMS) due to mixing of the fluctuations of the cavity field and the fluctuations of the condensate with finite atomic two-body interaction. The NMS is found to vanish for small values of the two-body interaction. We further show that the density excitations of the condensate can be used to squeeze the output quantum fluctuations of the light beam. This system may serve as an optomechanical control of quantum fluctuations using a Bose Einstein condensate.

Federico Casagrande, L. A. Lugiato

Zhou Ming, Fang Jia-Yuan, Huang Chun-Jia +1 more

The Hamiltonian operator of a system of single-mode light field interacting with Bose-Einstein condensate(BEC) of two-level atoms is suggested within the rotati ng-wave approximation. The influence of the interaction between atoms in the BEC on the quadrature squeezing properties of single-mode squeezed light interactin g with atomic BEC is studied under Bogoliubov approximation. The results show th at the fluctuations of two quadrature components of light evolve periodically in a cosine law and their squeezing properties are determined mainly by the initia l squeeze factor and squeeze direction angle of light, and that the interaction between atoms in BEC changes the amplitude and period of fluctuation of light.

Serge Reynaud, A. Heidmann, E. Giacobino +1 more

Ari K. Tuchman