Polarization Suppression of X-rayUmwegMultiple Waves in Crystals

Abstract

A theoretical model of X-ray fluorescence yield in perfect crystal by high frequency ultrasonic vibrations is supposed. The possibilities of the X-ray standing wave method are used basing on the registration of the angular dependence of the intensity of a secondary radiation yield [1,2].The calculations are based upon the presentation of vibrating crystal as a set of crystalline slides with different interplanar distances [3]. In the present paper the TDS is considered in crystal disturbed by high frequency ultrasonic vibrations. In this case additional X-ray reflexes (satellites) are formed out which can be used for structure investigations. By varying the incident angle one can excite all the satellites each after another and detect the variation in X-ray fluorescence yield. Theoretical analysis is made both in the case of the crystal matrix and the layer of impurity atoms.This work was supported by Russian Fund for Fundamental Research (N97-02-17966) [1] Kovalchuk M.V., Kohn V.G. "X-ray standing waves -new method of studying the structure of crystals", Sov. Phys. Usp, (1986), 29: 426-446. [2] Bedzyk, M.J., Materlik G. "Two beam dynamical diffraction solution of the phase problem: A determination with X-ray standing-wave fields", Phys. Rev. B (1985), 31: 6456-6463. [3] Kovalchuk M.V., Nosik V.L. "On the theory of X-ray standing waves in vibrating crystals" Nucl.