title: High-energy, kHz, picosecond hybrid Yb-doped chirped-pulse amplifier.
abstract: We report on a diode-pumped, hybrid Yb-doped chirped-pulse amplification (CPA) laser system with a compact pulse stretcher and compressor, consisting of Yb-doped fiber preamplifiers, a room-temperature Yb:KYW regenerative amplifier (RGA), and cryogenic Yb:YAG multi-pass amplifiers. The RGA provides a relatively broad amplification bandwidth and thereby a long pulse duration to mitigate B-integral in the CPA chain. The ~1030-nm laser pulses are amplified up to 70 mJ at 1-kHz repetition rate, currently limited by available optics apertures, and then compressed to ~6 ps with high efficiency. The near-diffraction-limited beam focusing quality is demonstrated with M(x)(2) = 1.1 and M(y)(2) = 1.2. The shot-to-shot energy fluctuation is as low as ~1% (rms), and the long-term energy drift and beam pointing stability for over 8 hours measurement are ~3.5% and <6 μrad (rms), respectively. To the best of our knowledge, this hybrid laser system produces the most energetic picosecond pulses at kHz repetition rates among rod-type laser amplifiers. With an optically synchronized Ti:sapphire seed laser, it provides a versatile platform optimized for pumping optical parametric chirped-pulse amplification systems as well as driving inverse Compton scattered X-rays.
authors.forename: Chun-Lin
authors.initials: CL
authors.lastname: Chang
authors.forename: Peter
authors.initials: P
authors.lastname: Krogen
authors.forename: Kyung-Han
authors.initials: KH
authors.lastname: Hong
authors.forename: Luis E
authors.initials: LE
authors.lastname: Zapata
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Moses
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Calendron
authors.forename: Houkun
authors.initials: H
authors.lastname: Liang
authors.forename: Chien-Jen
authors.initials: CJ
authors.lastname: Lai
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Stein
authors.forename: Phillip D
authors.initials: PD
authors.lastname: Keathley
authors.forename: Guillaume
authors.initials: G
authors.lastname: Laurent
authors.forename: Franz X
authors.initials: FX
authors.lastname: Kärtner