Anisotropic nonlinear refractive index measurement of a photorefractive crystal via spatial self-phase modulation

Abstract

We show that the refractive index modification photoinduced in a biased nonlinear photorefractive crystal can be accurately measured and controlled by means of a background incoherent illumination and an external electric field. The proposed easy-to-implement method is based on the far-field measurement of the diffraction patterns of a laser beam propagating through a self-defocusing medium undergoing spatial self-phase modulation. For various experimental conditions, both saturation intensity and maximum refractive index modification have been measured. We also clearly evidence and characterise the anisotropic nonlinear response of the crystal in the stationary regime.

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• Simple guidelines to predict self-phase modulation patterns
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Cited by in corpus (7)

• Hot atomic vapors for nonlinear and quantum optics
• Quantitative Analysis of Shock Wave Dynamics in a Fluid of Light
• Interferences between Bogoliubov excitations and their impact on the evidence of superfluidity in a paraxial fluid of light
• Experimental observation of turbulent coherent structures in a superfluid of light
• Tunable beam splitting via photorefractive nonlinearity and its applications in chiral waveguide induction and vortex generation
• Paraxial fluids of light
• Paraxial fluid of light in hot atomic vapors