I Quantum Fluctuations in Optical Systems

A. Mebrahtu

A system of low dimensional condensed ultracold atomic gases inside a field of a laser-driven optical cavity exhibits dispersive optical bistability. During such a process the system also shows quantum fluctuations. Condensate fluctuations are highly manifested particularly in low dimensional systems. In this paper we have investigated the theory and manifestation of fluctuations in quantum optical systems in low dimensional Bose-Einstein condensates. We have described the system using the mean-field approximation. In this study we have verified that low dimensional quantum gases exhibit not only highly fascinating properties but also we have indicated that the use of mean field theory to describe quantum gases in low dimensions is highly restricted since the possibility of generating low dimensional bosonic condensates is dominated by the existence of highly sensitive and intrinsic quantum fluctuations.

Federico Casagrande, L. A. Lugiato

Zhou Huai-ling

The optical field in multilayers dielectrics is quantized by the method of Green's function and the canonical quantum theory,the power spectrum of quantum fluctuation is obtained in each region.Then,the effect of the absorptive and dispersive characters of dielectrics on the quantum fluctuation of the optical field,the systematic work state and frequency characters are investigated by the numerical calculation.

Harry J. Kimble

Hermann Haken

Yen-Ju Chen, Chun-Yuan Cheng, Tien-Dat Pham +4 more

Quantum fluctuation plays a key role in the parametric down-conversion in the Langevin regime. In this paper, we report the experimental realization of optical parametric down-conversion in the Langevin regime on a chip. By precisely controlling the loss inherently tied to fluctuation, we observe the asymmetric Hong-Ou-Mandel dip - a hallmark of quantum fluctuation in the fluctuation-driven PDC, and the fluctuation-induced compression of single photons by nearly one order of magnitude. These findings pave the way for the manipulation of quantum fluctuation, quantum states, and system-reservoir interaction.