NSLS-II Seminar

Present and future world-leading radiation sources are being designed and optimized to enable
the routine production of coherent X-ray nanobeams of great interest in X-ray spectroscopy,
diffraction and imaging applications. X-ray beams with sizes as small as a few tens of
nanometers have been recently obtained in dedicated experiments. There is now an evergrowing
demand to make nano-beams accessible to a wider community. Along this line a
surfacing station for X-ray mirrors was recently developed and installed at the metrology
beamline BM5 of the ESRF. The instrument allows to eventually realize and control strongly
aspheric mirrors for X-ray nanofocusing using an on-line at-wavelength metrology.
This seminar will review some recent achievements in the field along with pertinent examples
of on-line diagnostics for which X-rays prove to be a unique probe. A set of novel
experimental techniques will be presented to describe: a) the use of real time diffuse X-ray
scattering to study the scaling behaviour of roughness in growing/eroded surfaces. b) An
exact solution to the classical phase retrieval problem in X-ray reflectometry and its
application to obtain the depth density distribution of an evolving thin film. c) The use of
shearing X-ray interferometry and of the near field X-ray scattering to infer the wave front
and the coherence degradation of radiation in X-ray optical systems and, finally d) the
development of a fast and robust ion beam profiling process to realize nanofocusing mirrors.
The proposed integrated approach promises to be a valuable and complementary alternative to the existing technologies for realizing the next generation of reflective X-ray optics for synchrotron and FEL radiation sources.