Diamond as a promising candidate for normal-incidence X-ray optics

So far, it has been understood that the only way to realize hard-X-ray mirrors with near 100% reflectivity is the use of total external reflection at grazing incidence to a surface. Dr. Y. V. Shvyd'ko (Argonne National Lab, USA) and his colleagues have recently proposed to use Bragg reflections from synthetic diamond crystal. They discussed how it shows an unprecedented reflecting power at normal incidence with meV order narrow bandwidths for hard X-rays. The optics might be a good candidate for X-ray free-electron laser oscillators (X-FELO). For more information, see the paper, "High-reflectivity high-resolution X-ray crystal optics with diamonds", Y. V. Shvyd'ko et al., Nature Physics, doi:10.1038/nphys1506; published online, 17 January 2010.