title: Angular spectrum simulation of X-ray focusing by Fresnel zone plates.
abstract: A computing simulation routine to model any type of circularly symmetric diffractive X-ray element has been implemented. The wavefield transmitted beyond the diffractive structures is numerically computed by the angular spectrum propagation method to an arbitrary propagation distance. Cylindrical symmetry is exploited to reduce the computation and memory requirements while preserving the accuracy of the numerical calculation through a quasi-discrete Hankel transform algorithm, an approach described by Guizar-Sicairos & Gutierrez-Vega [J. Opt. Soc. Am. A, (2004), 21, 53-58]. In particular, the code has been used to investigate the requirements for the stacking of two high-resolution Fresnel zone plates with an outermost zone width of 20 nm.
authors.affiliation: Paul Scherrer Institut, 5232 Villigen PSI, Switzerland.
authors.forename: Joan
authors.initials: J
authors.lastname: Vila-Comamala
authors.forename: Michael
authors.initials: M
authors.lastname: Wojcik
authors.forename: Ana
authors.initials: A
authors.lastname: Diaz
authors.forename: Manuel
authors.initials: M
authors.lastname: Guizar-Sicairos
authors.forename: Cameron M
authors.initials: CM
authors.lastname: Kewish
authors.forename: Steve
authors.initials: S
authors.lastname: Wang
authors.forename: Christian
authors.initials: C
authors.lastname: David
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007909:Lenses; D008962:Models, Theoretical; D011859:Radiography / Q000295:instrumentation*; D012542:Scattering, Radiation; D014961:X-Ray Diffraction / Q000295:instrumentation*; D014965:X-Rays
keywords: Fresnel zone plate stacking; X-ray wavefield modeling; angular spectrum method; diffractive X-ray optics