Beyond Gaussians—diffraction of complex light: tutorial
Abstract
Complex light can evolve radically as a function of propagation simply as a consequence of linear diffraction. Here, we characterize beam profiles in terms of their Dirichlet energy U ~ D , which scales with the asymptotic rate of diffraction, i.e., the rate of expansion of the beam mode field radius. This metric is translation-invariant, structure-informed, and constant as a beam propagates through vacuum. The diffraction length of structured light scales as L d f ∝ β s = U ~ D . We provide examples with Laguerre–Gaussian vortex beams and fractal multi-beams using non-dimensional units, which are vital for self-consistent analyses of complex light.
Fields of Study & Subjects
Experimental and Theoretical Physics Studies
Orbital Angular Momentum in Optics
Optical and Acousto-Optic Technologies
Publication details
- Journal / source
- Journal of the Optical Society of America A
- Publisher
- Optica Publishing Group
- Volume
- 43
- Issue
- 5
- Pages
- B32–B32
- Publication date
- 17 February 2026
- Language
- EN