K α x-ray emission characterization of 100 Hz, 15 mJ femtosecond laser system with high contrast ratio

• DOI: 10.1007/s00340-008-3342-6
• Publication Date: 2008-12-11T10:28:31Z
• Authors: S. Fourmaux; C. Serbanescu; R. E. Kincaid; A. Krol; J. C. Kieffer
• Keywords: High energy; Contrast ratio

We report K(alpha) x-ray production with a high energy (110 mJ per pulse at 800 nm before compression/15 mJ at 400 nm after compression), high repetition rate (100 Hz), and high pulse contrast (better than 10(-9) at 400 nm) laser system. To develop laser-based x-ray sources for biomedical imaging requires to use high-energy and high-power ultra-fast laser system where compression is achieved under vacuum. Using this type of laser system, we demonstrate long-term stability of the x-ray yield, conversion efficiency higher than 1.5 x 10(-5) with a Mo target, and the x-ray spot size close to the optical focal spot. This high-repetition K(alpha) x-ray source can be very useful for x-ray phase-contrast imaging.