title: Phase retrieval in x-ray lensless holography by reference beam tuning.
abstract: We show the ability to determine the relative phase between the object and a reference scatterer by tuning the overall intensity and phase of the reference wave. The proposed reference-guided phase retrieval algorithm uses the relative phase as a constraint to iteratively reconstruct the object and the reference simultaneously, and thus does not require precisely defined reference structures. The algorithm also features rapid and reliable convergence and overcomes the uniqueness problem. The method is demonstrated by a soft-x-ray coherent imaging experiment that utilizes a large micrometer-sized reference structure that can be turned on and off, yielding an object image with resolution close to the reconstruction pixel size of 21 nm.
authors.affiliation: Department of Applied Physics, Stanford University, Via Pueblo Mall, Stanford, California 94305, USA. dlzhu@stanford.edu
authors.forename: Diling
authors.initials: D
authors.lastname: Zhu
authors.forename: Benny
authors.initials: B
authors.lastname: Wu
authors.forename: Ramon
authors.initials: R
authors.lastname: Rick
authors.forename: Joachim
authors.initials: J
authors.lastname: Stöhr
authors.forename: Andreas
authors.initials: A
authors.lastname: Scherz