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Advances in the development of free-electron lasers offer the realistic prospect of high-resolution imaging to study the nanoworld on the time-scale of atomic motions. We identify X-ray Fourier Transform holography, (FTH) as a promising but, so far, inefficient scheme to do this. We show that a uniformly redundant array (URA) placed next to the sample, multiplies the efficiency of X-ray FTH by more than one thousand (approaching that of a perfect lens) and provides holographic images with both amplitude- and phase-contrast information. The experiments reported here demonstrate this concept by imaging a nano-fabricated object at a synchrotron source, and a bacterial cell at a soft X-ray free-electron-laser, where illumination by a single 15 fs pulse was successfully used in producing the holographic image. We expect with upcoming hard X-ray lasers to achieve considerably higher spatial resolution and to obtain ultrafast movies of excited states of matter.
We demonstrate the in-line holography for soft x-ray vortex beam having an orbital angular momentum. A hologram is recorded as an interference between a Bragg diffraction wave from a fork grating and a divergence wave generated by a Fresnel zone plat
The capability of generating two intense, femtosecond x-ray pulses with controlled time delay opens the possibility of performing time-resolved experiments for x-ray induced phenomena. We have applied this capability to study the photoinduced dynamic
A parabolic monocapillary X-ray lens (PMXRL) is designed to effectively constrain a laboratory point X-ray source into a parallel beam. A square-shaped lead occluder (SSLO) is used to block direct X-rays in the PMXRL. To design the PMXRL, we use Pyth
A radio interferometer uses time delays to maximize its response to radiation coming from a particular direction. These time delays compensate for differences in the time of arrival of the wavefront at the different elements of the interferometer, an
In both light optics and electron optics, the amplitude of a wave scattered by an object is an observable that is usually recorded in the form of an intensity distribution in a real space image or a diffraction image. In contrast, retrieval of the ph