?(3) scattering noises in nonlinear optical phase conjugation

David M. Pepper

M. Ducloy

Mitsuhiro Yokota, Pochi Yeh

We investigate the reduction of Rayleigh scattering in four-wave mixing due to photo-induced spatial redistribution of atoms in atomic vapors. The Rayleigh scattering from the pump beams in optical phase conjugation is a major source of noise, which affects the fidelity of the phase-conjugated image. In the blue-shifted operation, the atoms are driven toward the low-intensity regions of the standing-wave pattern, leading to a reduction of Rayleigh scattering. We also investigate the effect of saturation on the differential scattering cross section.

Mary Yvonne Lanzerotti, Robert W. Schirmer, Alexander L. Gaeta

Masaaki Yokota, P. Yeh

Investigates the noise due to Rayleigh scattering and its reduction via the spatial redistribution of atoms due to the standing wave pattern of the pump beams. For operation near the resonance, the interaction of the induced atomic dipole with the optical field leads to a periodic potential for the atoms due to the interference standing wave pattern. An assumption of the Boltzmann distribution yields a periodic distribution of the number density of atoms. In the paper, we investigate the effect of detuning and saturation on the noise due to Rayleigh scattering and address the issue of signal to noise ratio in nonlinear optical phase conjugation. We also investigate the minimum incident intensity needed to achieve a signal to noise ratio of one (S/N=1).

A. Stahl