Title :
Observation of high average power soft X-ray laser beam approaching full spatial coherence
Author :
Liu, Yanwei ; Seminario, Max ; Tomasel, Fernando G. ; Chang, Chang ; Rocca, Jorge J. ; Attwood, David T.
Author_Institution :
Center for X-ray Opt., Lawrence Berkeley Lab., CA, USA
Abstract :
We report the observation of an extraordinarily high degree of spatial coherence from a soft X-ray laser. The laser is a tabletop 45.9 nm capillary discharge-pumped Ne-like argon laser, which is capable of generating millijoule-level pulse energies that corresponds to an average power of several milliwatts. The method for measuring the spatial coherence follows the classic Thompson-Wolf two-pinhole interference experiment. We had observed a rapid increase of the spatial coherence with amplifier length, showing the effective mode-selection mechanism of strong refractive antiguiding. Full spatial coherence was approached with a 36 cm long plasma of very high axial uniformity and a length to diameter ratio exceeding 1000:1. Interference patterns with very high visibility are obtained with pinhole separations comparable to the total beam size. These results indicate a very high degree of spatial coherence throughout practically the entire laser beam
Keywords :
X-ray lasers; X-ray production; argon; brightness; ion lasers; light coherence; 46.9 nm; Ar; Ne-like argon laser; Thompson-Wolf two-pinhole interference; capillary discharge-pumped laser; effective mode-selection mechanism; full spatial coherence; high average power; soft X-ray laser beam; strong refractive antiguiding; very high axial uniformity plasma; Argon; Interference; Laser beams; Laser modes; Optical pulse generation; Plasma measurements; Power lasers; Pulse amplifiers; Spatial coherence; X-ray lasers;
Conference_Titel :
Lasers and Electro-Optics Society 2000 Annual Meeting. LEOS 2000. 13th Annual Meeting. IEEE
Conference_Location :
Rio Grande
Print_ISBN :
0-7803-5947-X
DOI :
10.1109/LEOS.2000.894001
