Finite-energy accelerating beam dynamics in wavelet-based representations

Abstract: Accelerating beams are wave packets which appear to spontaneously accelerate without external potentials or applied forces. Since their first physical realisation in the form of Airy beams, they have found applications on various platforms, spanning from optics to plasma physics. We investigate the dynamics of examples of finite-energy accelerating beams derived from catastrophe theory. We use a Madelung transformation in momentum-space, combined with a wavelet transformed analysis, to demonstrate that the beams' properties arise from a special type of vanishing self-interference. We identify the modes responsible for the wave packet's acceleration and we derive the general acceleration for higher-order cupsoid-related beams. We also demonstrate how bright solitons resulting from nonlinear Airy beams can be unambiguously detected using the wavelet transform. This methodology will allow for a better understanding of nontrivial wave packet dynamics.