NSLS-II Colloquium

Owing to the sophistication of synchrotron radiation light sources, X-rays have become more brilliant and acquired higher spatial coherence during the last two decades. In this context, the performance of focusing optics has been greatly improved. We have developed a precision deterministic mirror fabrication technique and realized nanometer-level precision mirrors for practical uses in X-ray microscope beamlines. In parallel, we have proposed the AKB mirrors, which incorporate Wolter optics concept from the conventional KB mirrors, and have succeeded in obtaining extremely small spot size and temporal stability of the focused light state. We have also proposed the world's first use of compensation optics combined with at-wavelength wavefront measurement to realize a high-precision focusing system, which is now in the stage of practical application. In this presentation, we will show the current status of our deterministic mirror fabrication technology and its performance. We will also introduce the single-nanometer focusing at SACLA made possible by the introduction of AKB optics and compensation optics, and as examples of the application, we will show various world's first observations of nonlinear optical phenomena in the X-ray region. In addition, we have recently been working on improving the performance of Bragg devices, and will present a newly developed a plasma etching method applied to the surface treatment of a microchannel-cut monochromator.