title: 100 W average power femtosecond laser at 343 nm.
abstract: We present a femtosecond laser system delivering up to 100 W of average power at 343 nm. The laser system employs a Yb-based femtosecond fiber laser and subsequent second- and third-harmonic generation in beta barium borate (BBO) crystals. Thermal gradients within these BBO crystals are mitigated by sapphire heat spreaders directly bonded to the front and back surface of the crystals. Thus, a nearly diffraction-limited beam quality (M2 < 1.4) is achieved, despite the high thermal load to the nonlinear crystals. This laser source is expected to push many industrial and scientific applications in the future.
authors.forename: Jan
authors.initials: J
authors.lastname: Rothhardt
authors.forename: Carolin
authors.initials: C
authors.lastname: Rothhardt
authors.forename: Michael
authors.initials: M
authors.lastname: Müller
authors.forename: Arno
authors.initials: A
authors.lastname: Klenke
authors.forename: Marco
authors.initials: M
authors.lastname: Kienel
authors.forename: Stefan
authors.initials: S
authors.lastname: Demmler
authors.forename: Tino
authors.initials: T
authors.lastname: Elsmann
authors.forename: Manfred
authors.initials: M
authors.lastname: Rothhardt
authors.forename: Jens
authors.initials: J
authors.lastname: Limpert
authors.forename: Andreas
authors.initials: A
authors.lastname: Tünnermann