Quasi-mosaicity as a tool for focusing hard x-rays

Quasi-mosaicity can be used to fabricate self-standing curved crystals with two curvatures of different crystalline planes. Indeed, a primary curvature imparted to a crystal results in quasi-mosaic curvature of a different plane direction. We show that, since the size of the focal spot of the photons diffracted by a crystal can be controlled by the quasi-mosaic curvature, quasi-mosaic crystals allow focusing with very high resolution. A Laue lens, exploiting quasi-mosaic effect, has been simulated and main results are shown. Self-standing quasi-mosaic crystals can be fabricated through several techniques, such as film deposition or surface grooving method.