Phase singularities are a ubiquitous feature of waves of all forms and represent a fundamental aspect of wave topology. An optical vortex phase singularity occurs when there is a spiral phase ramp about a point phase singularity. We report an experimental observation of an optical vortex in a field consisting of 9-keV x-ray photons. The vortex is created with an x-ray optical structure that imparts a spiral phase distribution to the incident wave field and is observed by use of diffraction about a wire to create a division-of-wave-front interferometer.
© 2002 Optical Society of America
Andrew G. Peele, Philip J. McMahon, David Paterson, Chanh Q. Tran, Adrian P. Mancuso, Keith A. Nugent, Jason P. Hayes, Erol Harvey, Barry Lai, and Ian McNulty, "Observation of an x-ray vortex," Opt. Lett. 27, 1752-1754 (2002)