Quasi-mosaic crystals for high-resolution focusing of hard x-rays through a Laue lens

Quasi-mosaicity is an effect of secondary bending within a crystal driven by crystalline anisotropy. This effect can be used to fabricate a series of curved crystals for the realization of a Laue lens. We highlight that crystals bent by quasi-mosaic effect envisage very high resolution focusing with respect to mosaic crystals. Under same conditions for energy passband and flux of incident photons, a Laue lens based on quasi-mosaic crystals would increase the signal-to-noise ratio by more than one order of magnitude as for the same lens with mosaic crystals. A proposal for the realization of a self-standing quasi-mosaic crystal is given. Here permanent bending of a crystal is achieved as a result of superficial indentations.