학술논문
Laser Requirements for High-Order Harmonic Generation by Relativistic Plasma Singularities
Document Type
article
Author
Alexander S. Pirozhkov; Timur Zh. Esirkepov; Tatiana A. Pikuz; Anatoly Ya. Faenov; Akito Sagisaka; Koichi Ogura; Yukio Hayashi; Hideyuki Kotaki; Eugene N. Ragozin; David Neely; James K. Koga; Yuji Fukuda; Masaharu Nishikino; Takashi Imazono; Noboru Hasegawa; Tetsuya Kawachi; Hiroyuki Daido; Yoshiaki Kato; Sergei V. Bulanov; Kiminori Kondo; Hiromitsu Kiriyama; Masaki Kando
Source
Quantum Beam Science, Vol 2, Iss 1, p 7 (2018)
Subject
Language
English
ISSN
2412-382X
Abstract
We discuss requirements on relativistic-irradiance (I0 > 1018 W/cm2) high-power (multi-terawatt) ultrashort (femtosecond) lasers for efficient generation of high-order harmonics in gas jet targets in a new regime discovered recently (Pirozhkov et al., 2012). Here, we present the results of several experimental campaigns performed with different irradiances, analyse the obtained results and derive the required laser parameters. In particular, we found that the root mean square (RMS) wavefront error should be smaller than ~100 nm (~λ/8). Further, the angular dispersion should be kept considerably smaller than the diffraction divergence, i.e., μrad level for 100–300-mm beam diameters. The corresponding angular chirp should not exceed 10−2 μrad/nm for a 40-nm bandwidth. We show the status of the J-KAREN-P laser (Kiriyama et al., 2015; Pirozhkov et al., 2017) and report on the progress towards satisfying these requirements.