Squeezing with Nonlinear Optics

Masahiro Takeoka, Daisuke Fujishima, Fumihiko Kannari

Concepts and experimental works of ultrashort optical pulse squeezing in nonlinear fibers are reviewed. In a nonlinear fiber, optical fields are squeezed or quantum mechanically correlated by optical Kerr effect. These are, however, unobservable by direct photo-detection. Three kinds of strategies to extract the detectable squeezing have been proposed and implemented experimentally. Recent studies on applications of these squeezed pulses or the intrapulse quantum correlations to the generation of entangled states are also reviewed.

Marlan O. Scully, Muhammad Suhail Zubairy

Sonam Mahajan, Neha Aggarwal, Aranya B. Bhattacherjee

We investigate theoretically an optomechanical system composed of an optical mode and a mechanical mode interacting through first-order coupling and second-order coupling in the presence of a Kerr nonlinear medium. We study how the nonlinearities (second-order optomechanical coupling and Kerr nonlinearity) alter the optical output spectrum, optical quadrature squeezing and optomechanical entanglement. It is shown that the intensity of the output optical spectrum decreases drastically with an increase in second-order optomechanical coupling while it increases significantly with an increase in Kerr nonlinear parameter. More interestingly, by choosing suitable second-order optomechanical coupling and detuning of the optical cavity field, one can achieve strong squeezing of the cavity light field. Further, these nonlinearities play an important role in creating robust optomechanical entanglement between optical and mechanical modes. Hence, the presence of various nonlinearities in the system can be a good platform for achieving the squeezing of light and robust optomechanical entanglement which can be used in realizing better quantum optomechanical devices.

Mark S. Hillery, Muhammad Suhail Zubairy, K. Wódkiewicz

Matthew J. Collett, Daniel F. Walls

The squeezing spectra for the output fields of several intracavity nonlinear optical systems are obtained. It is shown that at critical points, e.g., the turning points for optical bistability, the threshold for parametric oscillation, and the self-pulsing instability in second-harmonic generation, perfect squeezing in the output field is, in principle, possible.

Avijit Lahiri