FEATURES OF THE GOUY PHASE OF NONDIFFRACTING BEAMS

PABLO VAVELIUK; OSCAR MARTINEZ MATOS; GUSTAVO A. TORCHIA

PROGRESS IN ELECTROMAGNETICS RESEARCH

E M W PUBLISHING

Año: 2013 vol. 140 p. 599 - 611

It is shown how the linear Gouy phase of an ideal nondifracting beam of §(k ¡ kz)z form, with kz being the projection of the wavevector of modulus k of the plane wave spectrum onto the propagation axis z, is built from a rigorous treatment based on the successive approximations to the Helmholtz equation. All of di®erent families of nondi®racting beams with a continuum spectrum, as Bessel beams, Mathieu beams and Parabolic ones, as well as nondi®racting beams with a discrete spectrum, as kaleidoscopic beams, have an identical Gouy phase that fully governs the beam propagation dynamics. Hence, a real beam whose Gouy phase is close to that linear Gouy phase in a given range, will have nondi®racting-like properties on such a range. These results are applied to determine the e®ective regime in which a physically realizable beam can be treated as a nondi®racting one. As a fruitful example, the Gouy phase analysis is applied to fully establish the regime in which a Helmholtz-Gauss beam propagates with nondi®racting-like properties.