Laboratoire d'Optique Appliquée (LOA), ENSTA-Ecole Polytechnique, Chemin de la Hunière,91761 Palaiseau, France.
Opt Lett. 2009 Aug 15;34(16):2438-40. doi: 10.1364/ol.34.002438.
By seeding an optical-field-ionized population-inverted plasma amplifier with the 25th harmonic of an IR laser, we have achieved what we believe to be the first aberration-free laser beam in the soft x-ray spectral range. This laser emits within a cone of 1.34 mrad(1/e(2)) at a repetition rate of 10 Hz at a central wavelength of 32.8 nm. The beam exhibits a circular profile and wavefront distortions as low as lambda/17. A theoretical analysis of these results shows that this high beam quality is due to spatial filtering of the seed beam by the plasma amplifier aperture.
通过用红外激光的第 25 次谐波对光场电离布居反转等离子体放大器进行种子注入，我们实现了软 X 射线光谱范围内据称首例无像差激光光束。该激光在 32.8nm 的中心波长处以 10Hz 的重复率在 1.34mrad（1/e(2)）的圆锥内发射。光束呈现圆形轮廓，波前失真低至 λ/17。对这些结果的理论分析表明，这种高光束质量归因于等离子体放大器孔径对种子光束的空间滤波。
