title: Picosecond kilohertz-class cryogenically cooled multistage Yb-doped chirped pulse amplifier.
abstract: A multistage cryogenic chirped pulse amplifier has been developed, utilizing two different Yb-doped gain materials in subsequent amplifier stages. A Yb:GSAG regenerative amplifier followed by a Yb:YAG power amplifier is able to deliver pulses with a broader bandwidth than a system using only one of these two gain media throughout. We demonstrate 90 mJ of pulse energy (113 W of average power) uncompressed and 67 mJ (84 W of average power) compressed at 1.25 kHz pulse repetition frequency, 3.0 ps FWHM Gaussian pulse width, and near-diffraction-limited (M2<1.3) beam quality.
authors.forename: F X
authors.initials: FX
authors.lastname: Morrissey
authors.forename: T Y
authors.initials: TY
authors.lastname: Fan
authors.forename: D E
authors.initials: DE
authors.lastname: Miller
authors.forename: D
authors.initials: D
authors.lastname: Rand