Partially coherent quasi-Airy beams with controllable acceleration

Abstract

Self-acceleration and nondiffraction can be considered as the new properties of partially coherent light beams nowadays, provided that the light source is properly chosen and modulated. Here, we introduce a class of partially coherent light beams the propagation trajectory of which performs a parabolic-type curve as the well-known Airy beams. Theoretically, they are originated from a well-designed cross-spectral density function in the spatial-frequency domain. Experimentally, they are produced by shining an amplitude-modulated Schell-model source on the phase mask which is the Fourier transform of predesigned Airy functions. It is shown that, for such beams, one can control their acceleration properties by adjusting the initial angle of the sidelobes. Moreover, when the source is under a nearly incoherent state, the oscillation of the sidelobes of the beams turns smooth and the intensity distribution concentrates on the mainlobe with the Airy tails. The experimental results are in agreement with the theoretical predictions. A trial solution for coherent-mode representation of such a beam is derived and our paper provides an alternative outlook for understanding of self-acceleration on partially coherent light beams.