| Autor: |
Liang Yin, Hanchen Wang, Brendan A. Reagan, Cory Baumgarten, Zhonghao Lyu, Regina Soufli, Eric Gullikson, Vyacheslav N. Shlyaptsev, Jorge J. Rocca |
| Jazyk: |
angličtina |
| Rok vydání: |
2021 |
| Předmět: |
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| Zdroj: |
IEEE Photonics Journal, Vol 13, Iss 1, Pp 1-15 (2021) |
| Druh dokumentu: |
article |
| ISSN: |
1943-0655 |
| DOI: |
10.1109/JPHOT.2020.3047093 |
| Popis: |
We have studied the laser pulse shape dependence of the conversion efficiency of λ = 1.03 μm laser pulse energy into 13.5 nm extreme ultraviolet (EUV) emission from a Sn laser-produced plasma. Laser pulses of arbitrary temporal shape ranging from hundreds of picoseconds to several nanoseconds were generated using a programmable pulse synthesizer based on a diode-pumped chirped pulse amplification Yb: YAG laser. Measurements show that the conversion efficiency favors the use of nearly square pulses of duration longer than 2 ns, in agreement with hydrodynamic/atomic physics simulations. A 35% increase in conversion efficiency was obtained when Q-switched pulses were substituted by square pulses of a similar duration. Experiments conducted irradiating a Sn target with a sequence of two time-delayed 250 ps pulses showed a 30 percent increase in the EUV yield respect to a single pulse of the same total energy when the pulse separation was optimum at 2.1 ns. This suggests that re-heating of the plasma with delayed laser pulses could be used to improve the EUV yield. The spectroscopic characterization of EUV emission and in-band EUV images that characterize the source size are also presented. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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