Focusing properties of hard x-ray photon sieves: three-parameter apodization window and waveguide effect

摘要

In this Letter, a three-parameter modified Kaiser apodization window is used to modulate the pinhole den-nsity on each ring of hard x-ray photon sieves, analyzing the guided-wave propagation inside the photonnsieves’ nanostructure. Theoretical analysis reveals that the waveguide effect can suppress the emergence ofnthe high-order diffraction effect; the additional parameter of the modified Kaiser window function gives risento new degrees of freedom for manipulating the FWHM and signal-to-noise ratio. Metal nanostructure thick-nness has no influence on the FWHM. Hard x-ray photon sieves with 90° phase shift (not 180° phase shift)ncan provide the best signal-to-noise ratio, which relaxes the nanofabrication constraints somewhat. Ournwork provides a robust way to design hard x-ray photon sieves. © 2009 Optical Society of America