title: Intensity-based modal decomposition of optical beams in terms of Hermite-Gaussian functions
abstract: We show that when an arbitrary optical beam is decomposed into a superposition of Hermite-Gaussian functions, it is sufficient to record a number of intensity profiles sampled at various transverse planes to uniquely determine the relative modal weights. This result follows from the parity relation and the nature of the Gouy phase, in addition to the orthogonality of the Fourier-transformed intensity profiles associated with the Hermite-Gaussian modes.
authors.affiliation: Department of Electrical and Computer Engineering, McGill University, Montreal, Quebec, Canada. xxue@photonics.ece.mcgill.ca
authors.initials: X
authors.lastname: Xue
authors.initials: H
authors.lastname: Wei
authors.initials: AG
authors.lastname: Kirk