RESUMEN
New diffractive imaging techniques using coherent x-ray beams have made possible nanometer-scale resolution imaging by replacing the optics in a microscope with an iterative phase retrieval algorithm. However, to date very high resolution imaging (< 40 nm) was limited to large-scale synchrotron facilities. Here, we present a significant advance in image resolution and capabilities for desktop soft x-ray microscopes that will enable widespread applications in nanoscience and nanotechnology. Using 13 nm high harmonic beams, we demonstrate a record 22 nm spatial resolution for any tabletop x-ray microscope. Finally, we show that unique information about the sample can be obtained by extracting 3-D information at very high numerical apertures.
RESUMEN
Light microscopy has greatly advanced our understanding of nature. The achievable resolution, however, is limited by optical wavelengths to approximately 200 nm. By using imaging and labeling technologies, resolutions beyond the diffraction limit can be achieved for specialized specimens with techniques such as near-field scanning optical microscopy, stimulated emission depletion microscopy, and photoactivated localization microscopy. Here, we report a versatile soft x-ray diffraction microscope with 70- to 90-nm resolution by using two different tabletop coherent soft x-ray sources-a soft x-ray laser and a high-harmonic source. We also use field curvature correction that allows high numerical aperture imaging and near-diffraction-limited resolution of 1.5lambda. A tabletop soft x-ray diffraction microscope should find broad applications in biology, nanoscience, and materials science because of its simple optical design, high resolution, large depth of field, 3D imaging capability, scalability to shorter wavelengths, and ultrafast temporal resolution.
Asunto(s)
Microscopía/instrumentación , Óptica y Fotónica/instrumentación , Difracción de Rayos X/instrumentación , Algoritmos , Diseño de Equipo , Interpretación de Imagen Asistida por Computador , Rayos Láser , Lentes , Nanopartículas , Nanotecnología/métodos , Rayos UltravioletaRESUMEN
We present the first experimental demonstration of lensless diffractive imaging using coherent soft x rays generated by a tabletop soft-x-ray source. A 29 nm high harmonic beam illuminates an object, and the subsequent diffraction is collected on an x-ray CCD camera. High dynamic range diffraction patterns are obtained by taking multiple exposures while blocking small-angle diffraction using beam blocks of varying size. These patterns reconstruct to images with 214 nm resolution. This work demonstrates a practical tabletop lensless microscope that promises to find applications in materials science, nanoscience, and biology.