A light amplification scheme utilizing the nonlinear coherent coupler

Antonio Mecozzi

A scheme to realize phase-sensitive amplification of light using a nonlinear coherent coupler is proposed. Squeezed-light generation with low pump power and short interaction length is possible with this technique.

Michael S. Feld, Vladilen S Letokhov

Faisal A A El-Orany, Jan Peřina, M Sebawe Abdalla

We show that a nonlinear asymmetric directional coupler composed of a linear waveguide and a nonlinear waveguide operating by nondegenerate parametric amplification is an effective source of single-mode squeezed light. This is demonstrated, under certain conditions and for specific modes, for incident coherent beams in terms of the quasiprobability functions, photon-number distribution and phase distribution.

Vladilen S Letokhov, Michael S. Feld

Ladislav Mišta, Jaroslav Řeháček, Jan Peřina

We examine phase properties of a contradirectional nonlinear asymmetric coupler. We derive the phase distribution using the concept of phase space. An interesting behaviour of the linear mode, namely bifurcation of a distribution, phase shift, experienced during its propagation and phase switching are demonstrated. It is shown that light initially in the coherent state approximately maintains its phase properties during amplification although its Poissonian photon-number statistics are not conserved. Finally, thermal noise in the linear mode can be reduced and squeezing of the phase fluctuations under the level of those for the coherent state with appropriately chosen parameters of the process can be obtained.

Nicolai G. Basov, Vladilen S Letokhov