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arXiv · 1310.7678

Damage threshold and focusability of mid-infrared free-electron laser pulses gated by a plasma mirror with nanosecond switching pulses

Xiaolong Wang·Takashi Nakajima·Heishun Zen·Toshiteru Kii·Hideaki Ohgaki
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Abstract

The presence of a pulse train structure of an oscillator-type free-electron laser (FEL) results in the immediate damage of a solid target upon focusing. We demonstrate that the laser-induced damage threshold can be significantly improved by gating the mid-infrared (MIR) FEL pulses with a plasma mirror. Although the switching pulses we employ have a nanosecond duration which does not guarantee the clean wavefront of the gated FEL pulses, the high focusablity is experimentally confirmed through the observation of spectral broadening by a factor of 2.1 when we tightly focus the gated FEL pulses onto the Ge plate.

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Xiaolong Wang, Takashi Nakajima, Heishun Zen, Toshiteru Kii, Hideaki Ohgaki. 2013-10-29. Damage threshold and focusability of mid-infrared free-electron laser pulses gated by a plasma mirror with nanosecond switching pulses. https://doi.org/10.1063/1.4828995

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