title: Ince-Gaussian series representation of the two-dimensional fractional Fourier transform.
abstract: We introduce the Ince-Gaussian series representation of the two-dimensional fractional Fourier transform in elliptical coordinates. A physical interpretation is provided in terms of field propagation in quadratic graded-index media whose eigenmodes in elliptical coordinates are derived for the first time to our knowledge. The kernel of the new series representation is expressed in terms of Ince-Gaussian functions. The equivalence among the Hermite-Gaussian, Laguerre-Gaussian, and Ince-Gaussian series representations is verified by establishing the relation among the three definitions.
authors.affiliation: Photonics and Mathematical Optics Group, Tecnológico de Monterrey, Monterrey 64849, Mexico. bandres@gmail.com
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Bandres
authors.forename: Julio C
authors.initials: JC
authors.lastname: Gutiérrez-Vega