SPATIAL COHERENCE OF A REPETITIVE LASER-PLASMA POINT X-RAY SOURCE IN THE WATER WINDOW SPECTRAL REGION

We propose and demonstrate a coherent laser-plasma point x-ray source in the water window spectral region operating at a repetition rate of up to 100 Hz. The emission from the 10-mu-m-diameter source is filtered to generate monochromatic radiation at a 3.37 nm wavelength. Soft x-ray fringes of -the Young's interference experiment were obtained with a visibility of 0.62 +/- 0.1 with a slit pair of 10.5-mu-m separation at a distance of 31.7 cm from the source. The source can be used to take either a hologram or transmission scanning x-ray micrograph within a reasonable exposure time of several minutes.