Two dimensional compound refractive lenses (CRL) made out of single crystal diamond had been recently demonstrated [1, 2]. The use of compound refractive lens is inevitably associated with high x-ray absorption. One of the benefits of diamond as a material for CRL is its ability to withstand high instantaneous and average heat load. We used finite element method to simulate thermal effects in the lens. A steady state simulation is done for high average heat load conditions of ultimate storage rings. A time domain simulation is used for high peak power XFEL case. We compare diamond with beryllium, a common material for the CRL, and find that diamond temperature rise is less even though its x-ray absorption is higher.
Several single crystal CVD diamonds with (001) and (111) surface orientations were studied using x-ray diffraction rocking curve mapping in the double-crystal pseudo plane-wave configuration using Bragg reflection geometry. Strongly nonuniform distributions of rocking curve parameters on the studied crystal surfaces were observed, which indicates that the crystals exhibit substantial lattice distortions. Selected crystal pairs were tested in the nondispersive double-crystal configuration using polychromatic bending magnet synchrotron radiation. The results suggest that CVD diamond crystals could be used as high-flux broadband x-ray monochromators in applications where preservation of the radiation wavefront is not a primary goal.
An electrical response of a diffracting diamond (111) crystal was studied in a single electrode configuration where the electrode was deposited on a small portion of the crystal entrance surface. The experiment was performed in ambient air using an x-ray beam after a Si (111) double-crystal monochromator with the diamond crystal set in the Bragg diffraction condition. It was found that the electric current as a function of the Bragg angle exhibits behavior characteristic of secondary yield curves (e.g.,1). It is proposed to utilize this effect to monitor the intensity of the Bragg reflected x-ray beam. Such non-invasive monitoring does not rely on the use of stand-alone radiation monitors (e.g., ionization chambers) and is expected to facilitate x-ray optics alignment procedures. As an attempt to improve signal-to-noise ratio by containing the electric field in the optical element an electric response of a high-resistivity silicon crystal was studied in a two-electrode configuration. Preliminary results are reported.