Status of the High Average Power Diode-Pumped Solid State Laser Development at HiLASE

Abstract

An overview of the latest developments of kilowatt-level diode pumped solid state lasers for advanced applications at the HiLASE Centre is presented. An overview of subcontracted and in-house-developed laser beamlines is presented. The aim of development is to build kW-class beamlines delivering picosecond pulses between 1-and 100-kHz repetition rates and high-energy nanosecond pulses at 10 Hz. The picosecond beamlines are based on Yb:YAG thin-disk amplifiers and chirped pulse amplification. The current status of the beamlines' performance is reported. The advantages of zero-phonon line and pulsed OPEN ACCESS Appl. Sci. 2015, 5638 pumping are demonstrated with respect to efficiency, thin disk temperature and beam quality. New diagnostics methods supporting the high average power lasers' development, such as the high-resolution spectroscopy of Yb-doped materials, in situ thin disk deformation measurements, single-shot M 2 measurement, realization of wavefront correction by a deformable mirror and the laser performance of a new mixed garnet ceramics, are described. The energetic, thermal and fluid-mechanical numerical modeling for the optimization of the multi-slab amplifiers is also described.

Advances in High-Power, Ultrashort Pulse DPSSL Technologies at HiLASE

“…The Perla B was redesigned [32] in order to provide a burst of pulses and better fit experimental requirements. Intra-burst repetition rate was set to 10 kHz, and a burst repetition rate of 100 Hz with optional switching back to original configuration operating continuously at a repetition rate of 1 kHz was described in detail in References [24,27]. In the burst mode, each 1-ms long pulse burst consists of ten 1-2-ps long pulses.…”

“…In this paper, we report on progress in the development of ultrashort pulsed laser technology and laser components development since 2015, when a first review paper was published [27]. The technology of Yb:YAG thin-disk lasers Perla A, B, and C emitting in near-infrared ranges has matured, and goals have been updated to finally exceed 1 kW of average power and 1 J of pulse energy in following years ( Figure 1).…”

The Application of Cryogenic Laser Physics to the Development of High Average Power Ultra-Short Pulse Lasers

“…This laser also employs the technique of imaging and vacuum spatial filtering to manage nonlinear effects and produce clean beam profiles, techniques that were pioneered is the earliest high-peak-power laser systems developed in connection with inertial confinement fusion [37]. We also mention the work of HiLASE [171,172], where large aperture high energy/pulse Yb:YAG cryogenically He gas cooled lasers are being developed. In [152] a 10 J/pulse, 10 Hz cryogenic amplifier is already developed, and a 100 J/pulse cryogenic amplifier is expected to be demonstrated in 2015, while in [173] Figure 48 shows the peak power obtained as a function of average power, again using data from Table 10.…”

Faraday effect measurements of holmium oxide (Ho2O3) ceramics-based magneto-optical materials

“…In the context of the continuously increasing average power of high-energy class diode pumped solid-state lasers (HECDPSSLs), careful treatment of the thermal effects due to the parasitic absorption of power in optical components has become tremendously important for the further development of HEC-DPSSLs [1][2][3][4] . One of the most seriously affected optical components is the Faraday isolator (FI), because of the relatively high absorption (∼10 −3 cm −1 ) of the currently available magneto-optical elements (MOEs).…”