Generation of bottle beams in self-defocusing photorefractive crystals

The propagation property of single and two circular Airy beams in self-defocusing photorefractive crystals is investigated. The single and two circular Airy beams both can form bottle beams with dual focus by virtue of self-defocusing nonlinearity. With the initial radius increasing, the center positon of low-intensity region moves in propagation direction, and the light intensity of the first focus also increases. The light intensity of the second focus decreases and that of the first focus is almost unchanged with the self-defocusing nonlinearity increasing. Moreover, the shape of bottle beams can be adjusted by changing the initial radius and light intensity. The second focus of the bottle beam generated from two circular Airy beams will separate from the body of bottle beam with the deviation distance increasing.