Abstract

We present coherence measurements of extreme-ultraviolet (EUV) light generated using the process of high-harmonic upconversion of a femtosecond laser. We show that, by using a phase-matched hollow-fiber geometry, the generated beam exhibits nearly full spatial coherence - the highest inherent spatial coherence of any source in this region of the spectrum to date. The combined short wavelength and high coherence give it, to our knowledge, the smallest possible effective source-size of any light source to date. We also show that this laser-like EUV source can be used to record Gabor holograms of small objects, using an extremely simple setup. This is the first demonstration of EUV holography using a tabletop light source, and has potential for a broad range of applications in science and technology.

© 2002 Optical Society of America