Planar waveguide-resonator: a new device for x-ray optics

摘要

Systematic investigations of the width dependence on the x-ray beam propagation mechanism for a narrow extended slit formed by two plane dielectric plates are presented. It is shown that the mechanism of a multiple consecutive total reflection for Cu Kalpha radiation dominates in a slit width range s greater than or equal to 3 mum. At the same time the manner of Cu Kalpha radiation propagation for super-narrow slits s < 0.1 mum is very different from the multiple total reflection mechanism. The x-ray beam intensity proves to be constant for all this range of magnitude. This gives grounds to expect that the super-narrow slit area is characterized by a specific type of mechanism of x-ray beam propagation: waveguide-resonance. A simple model for the waveguide-resonance propagation mechanism based on the formation of a uniform x-ray standing wave interference field in the total space of a narrow extended slit was developed. The design of a new x-ray optical device, namely a planar x-ray waveguide-resonator, is proposed based on the waveguide-resonance mechanism. Some properties of the composite planar x-ray waveguide-resonator are discussed. It is shown that under specific conditions the composite waveguide can demonstrate a partial tunneling effect of the x-ray beam. The main applications of the new technique are discussed. Copyright (C) 2004 John Wiley Sons, Ltd.