Nonlinear coupling and modulation of the guided modes in photorefractive slab waveguide.

Owing to its excellent electro-optic, ferroelectric and nonlinear optical properties, photorefractive crystal (PRC) provides a versatile platform for developing nonlinear waveguides, which has a great potential in integrated optics components. In this paper, we theoretically study nonlinear coupling of optical guided modes in photorefractive waveguides by the spatial-partition fast Fourier transform beam propagation method (SP FFT-BPM). The modulation of applied external electrical field on the guided modes is investigated, and demonstrated as a new method to modulate the guided modes without artificially refabricating physical configuration or structure of the waveguide. [ABSTRACT FROM AUTHOR]