Investigation of the phase shift in x-ray forward diffraction using an x-ray interferometer

The phase shift of forward-diffracted x rays by a perfect crystal is discussed on the basis of the dynamical theory of x-ray diffraction. By means of a triple Laue-case x-ray interferometer, the phase shift of forward-diffracted x rays by a diamond crystal slab was investigated. It was verified that the phase shift in x-ray forward diffraction actually follows the dynamical theory of x-ray diffraction. It is suggested that a ''phase-sensitive'' experimental method using an interferometer can be applied to explore a wide variety of diffraction phenomena of x rays, gamma rays, and neutrons in a periodic medium.