Date |
Do, 17.10.2013 - Do, 17.10.2013 |
Time |
10.15 |
Speaker |
Fei Jia, Institute of Applied Physics, University of Bern |
Location |
Universität Bern, Institut für Angewandte Physik, Gebäude exakte Wissenschaften, Hörsaal B116, Sidlerstrasse 5, 3012 Bern |
Program |
Compared with modern short wavelength sources, working in the wavelengths of sub-10 nm or less, the plasma soft-X-ray laser offers outstanding spectral resolution with high peak brilliance of several orders of magnitude greater than any other existing sources such as HHG, synchrotron radiation and FELs. The recent introduction of the grazing-incidence pumping (GRIP) and travelling wave excitation (TWE) schemes have greatly improved the efficiency of soft-X-ray lasers operating in the 10-20 nm regions. In this talk, I will present the latest results which we attempt to move towards shorter wavelengths down to 7.36 nm by using Ni-like samarium (Sm) as the gain medium and pumped by the 10-TW Nd:glass CPA (chirped- pulse amplification) laser system. With a infrared pump pulse energy of 13 J in 1.5 ps pulse duration, a near-saturated soft- X-ray lasing on the 4d -> 4p, J = 0-1 line of Sm at the wavelength of 7.36 nm was achieved and delivers pulse energy of 3- 4 μJ. Since the intrinsic character of ASE signal group velocity variation and the relatively short gain life-time, the temporal- spatial synchronization of ASE signal with respect to the TWE velocity becomes significant. Therefore, I will show a novel method to introduce a varied TWE velocity with a positive slope along the gain medium by modifying our grating compressor and focusing optics according to the results of numerical simulations. |
Download |
(75 KB) |
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(75 KB) |
Link |
www.iap.unibe.ch |
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