Generation of a variety of Airy beams using a dynamic diffractive optical phase element

Abstract

We demonstrate theoretically the generation of a variety of dynamic 2D Airy beams. We generate single, 2D dual-, and quad-Airy-like beams using a dynamic optical phase, obtained by the propagation of two crossed standing ultrasonic waves (UWs) in a liquid medium (water). These UWs create sinusoidal variation of the liquid medium refractive index in two dimensions. Using the asymptotic behavior of the sine function near zero, the 2D sinusoidal phase created by the piezoelectric transducer is reduced to a 2D periodic cubic phase. As it is known, the latter converts an input plane wave (Gaussian beam) into an Airy (Airy-like) beam in the far field. By acting on the dynamic optical phase parameters, one can change the characteristics of the obtained Airy beam (trajectory and acceleration). Using combined Gaussian beams, we clearly demonstrate the existence of a variety of combined dynamic Airy beams, such as Airy, dual-Airy, symmetric-Airy, anti-symmetric-Airy, and quad-Airy beams. We believe that the present work is of significant interest in the fields of dynamic focusing, curved manipulation, and transportation of microparticles.