title: Simple spectral method for solving propagation problems in cylindrical geometry with fast Fourier transforms.
abstract: We describe a spectral method for solving the paraxial wave equation in cylindrical geometry that is based on expansion of the exponential evolution operator in a Taylor series and use of fast Fourier transforms to evaluate derivatives. A fourth-order expansion gives excellent agreement with a two-transverse-dimensional split-operator calculation at a fraction of the cost in computation time per z step and at a considerable savings in storage.
authors.forename: M D
authors.initials: MD
authors.lastname: Feit
authors.forename: J A
authors.initials: JA
authors.lastname: Fleck