The tangent-like and sine-like characteristics in the head and tail regions of photorefractive surface waveguide arrays are elaborately demonstrated, and the regulation of such waveguide arrays on the written beam, background illumination, and external electric field is systematically studied for the first time. For the photorefractive surface apodized waveguide arrays, it is observed that guided mode bands of the fundamental mode gradually split and eventually reach saturation as a result of the influence of the power of photorefractive surface waves on the modulation depth of the refractive index; the period can be effectively adjusted by the wavelength and grazing angle of the written beam. However, there is an interesting chirp near surface for a large grazing angle. For the photorefractive surface nonlinearly chirped waveguide arrays, the amplitude, sign, and initial position of chirp can be conveniently regulated by an external electric field, background illumination, and incident beam, etc., and the modulation depth can also be flexibly adjusted by the influence of external electric fields on the refractive index of substrate. (C) 2016 Optical Society of America
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