Coherent diffractive imaging beyond the projection approximation: waveguiding at extreme ultraviolet wavelengths

• DOI: 10.1364/oe.23.019911
• Publication Date: 2015-07-23T19:47:16Z
• Authors: Sergey Zayko; Eike Mönnich; Murat Sivis; Dong-Du Mai; Tim Salditt; Sascha Schäfer; Claus Ropers
• Keywords: x-ray optics; 0103 physical sciences; x-ray imaging; 01 natural sciences

We study extreme-ultraviolet wave propagation within optically thick nanostructures by means of high-resolution coherent diffractive imaging using high-harmonic radiation. Exit waves from different objects are reconstructed by phase retrieval algorithms, and are shown to be dominated by waveguiding within the sample. The experiments provide a direct visualization of extreme-ultraviolet guided modes, and demonstrate that multiple scattering is a generic feature in extruded nanoscale geometries. The observations are successfully reproduced in numerical and semi-analytical simulations.