5 research outputs found
Interaction of Profiled Light with Contrapropagating Acoustic Waves: Fourier Transform Approach
A straightforward Fourier-transform approach is employed to investigate acousto-optic interaction between an input optical beam with arbitrary profile and contrapropagating cw sound in the Bragg regime. The process can be analyzed in terms of the simultaneous scattering of light by the two sound waves in the interaction region. Analytic expressions for the equivalent transfer functions are obtained and the scattered light profiles are plotted
Perturbational Analysis of Steady-State and Transient-Beam Fanning in Thin and Thick Photorefractive Media
Using a perturbational-analysis and Fourier-transform techniques, we solve the Kukhtarev equations to analyze the steady-state and the transient beam fanning in a photorefractive material. Steady-state results are calculated with both thin- and thick-sample models for the photorefractive material, and the results are compared. The thin-sample results are corroborated with a simple physical argument based on an Airy function approach. We find the nature of the dependence of beam fanning on the beam size and sample thickness. Furthermore, we calculate the transient buildup of beam fanning using the thick-sample model
Role of Diffusive, Photovoltaic, and Thermal Effects in Beam Fanning in LiNbO3
We analyze the steady-state (Gaussian) beam fanning in LiNbO3 from the nonlinearly coupled Kukhtarev equations by including both diffusive and photovoltaic effects and by adding the thermal effect in the calculation. There is good agreement between theory and experiment. The results show a symmetric beam-fanning pattern whose size depends on the beam waist and the power. Possible applications of our results in nondestructive testing of material parameters and optical limiting are discussed
Optical Limiting based on Deterministic Beam Fanning in Photorefractive Materials
We propose passive optical limiting based on the photorefractive effect-induced asymmetric deterministic beam fanning in BaTiO3, and symmetric deterministic beam fanning due to a combination of photovoltaic and thermal effects in LiNbO3
Noise Analysis of Photorefractive Holograms Under Gaussian Beam Illumination
Using a novel transfer function approach, we investigate the nature of the diffracted Gaussian beam from a photorefractive hologram under the influence of noise. The signal-to-noise ratio and spatial fidelity are defined, and their dependence on fringe spacing, temperature and reading beam intensity are discussed