Gaussian beams and minimum diffraction.
I show that different legitimate measures of the amount of diffraction lead to contradictory conclusions concerning the beam profile that experiences minimum diffraction for a given beam width. In particular, when the Rényi entropy is used, the Gaussian beams no longer provide minimum diffraction, i.e., they do not have maximum quality.
Luis
Alfredo
A
Departamento de Optica, Facultad de Ciencias Físicas, Universidad Complutense, Madrid, Spain. alluis@fis.ucm.es