Easy to produce thin film waveguides can confine incident x-ray beams in one direction in guiding layers as thin as 10 nm. Consequently they can provide attractive beam dimensions for microscopy purposes. This report presents a simple model and analytical equations for the transmission calculation, which provide results consistent with the rigorous calculations based on a recursion technique. By use of these results the waveguide transmission can be compared directly with other microscopy objectives. Ideally x-ray waveguides can transmit the spatially coherent part of an incident radiation beam. The transmissions measured for state-of-the-art one-and two-dimensional waveguides are found to correspond to experimental efficiencies of the order of 0.5 for each confinement direction. Waveguides with thinner guiding layers cannot efficiently be used at smaller photon energy in highly collimated beams, instead the beam divergence in unfocused beamlines at state-of-the-art synchrotron radiation sources may eventually have to be increased to the larger angular acceptance of these waveguides by use of other focusing optics.

Date Published: 4 November 2004
PDF: 10 pages
Proc. SPIE 5539, Design and Microfabrication of Novel X-Ray Optics II, (4 November 2004); doi: 10.1117/12.556661

Published in SPIE Proceedings Vol. 5539:
Design and Microfabrication of Novel X-Ray Optics II
Anatoly A. Snigirev; Derrick C. Mancini, Editor(s)