Abstract
Three-dimensional phase contrast imaging of multiply-scattering samples in X-ray and electron microscopy is extremely challenging, due to small numerical apertures, the unavailability of wavefront shaping optics, and the highly nonlinear inversion required from intensity-only measurements. In this work, we present a new algorithm using the scattering matrix formalism to solve the scattering from a non-crystalline medium from scanning diffraction measurements, and recover the illumination aberrations. Our method will enable 3D imaging and materials characterization at high resolution for a wide range of materials.
Highlights
Phase-contrast imaging is widely used in light [1,2], x-ray [3,4], and electron microscopy [5,6] due to its high efficiency and resolution
This is mainly due to the fact that the optical systems in x-ray and electron microscopy have relatively small numerical apertures, such that the information recorded from a single view covers only a small fraction of reciprocal space [31,32,33]
To demonstrate that our algorithm can reconstruct S matrices of realistic samples, we simulate a four-dimensional (4D) scanning TEM (STEM) focal series of the sample shown in Fig. 1(a), as it may appear in a tomography experiment
Summary
Phase-contrast imaging is widely used in light [1,2], x-ray [3,4], and electron microscopy [5,6] due to its high efficiency and resolution. When the WPOA holds, the linear relation implied between the specimen potential and measured intensity allows a constructive and unambiguous solution Another commonly used simplification in phase-contrast microscopy is the projection approximation, in which all scattering is assumed to originate from an infinitesimally thin two-dimensional (2D) plane [12,13]. This is mainly due to the fact that the optical systems in x-ray and electron microscopy have relatively small numerical apertures, such that the information recorded from a single view covers only a small fraction of reciprocal space [31,32,33] This problem can be overcome either by enforcing strong prior knowledge about the underlying scattering potential in the form of sparsity constraints or the proper choice of slice separation [30] or by performing tomographic experiments [34,35,36]. While here we synthesize large-scale phase-contrast images from a strongly scattering sample with a thickness of 1.2 times the depth of focus, optical sectioning of the scattering matrix with a limited field of view was recently experimentally shown to provide three-dimensional information on the unit-cell scale in a strongly scattering sample that spans multiple depths of focus [55]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
