Solid state lasers

Short pulse solid state lasers produce high-energy pulses (HEP) with nanosecond to femto-second duration at high average power (HAP). They are required for many scientific applications; such as pumping of optical parametric chirped pulse amplifiers or >100 TW Ti:sapphire lasers.

These lasers can provide optical pulses that enable laser wake field accelerators at kHz repetition rate, high energy THz generation, or act as an optical undulator in X-ray sources.

The team at UFOX is at the frontier of development in those scientific laser applications and currently works closely with both the THz acceleration and Optical parametric synthesiser teams.

Cryogenically-cooled lasers with modern Yb3+-doped materials such as Yb:YAG, Yb:YLF have proven to be an excellent high-power and high-energy laser and amplifier technology for average power scaling. This is due to its good thermo-optic properties, small quantum defect, high gain and low saturation fluence.

Our team is currently working on two cryogenic laser developments:

Yb:YAG composite-thin-disk (CTD) laser systems
This laser has demonstrated a long-term stable operation with 1.2-joule, ½-ns chirped pulse output at 500 Hz. The output pulses (FWHM 0.35nm) can be compressed to <5ps. Currently, we are upgrading this laser to reach higher energy, and to increase the repetition rate of the system to 1 kHz.
This will bring our average power output to the 1kW level.

Yb:YLF laser systems
This laser system has been developed to reach sup-picosecond pulse duration (~500fs) with energies of 100 mJ at high repetition rates (1kHz-5kHz), the system is composed of a cryo-genic regenerative amplifier followed by a multi-pass booster amplifier. All systems are seeded from mode-locked fiber oscillators, fiber-based stretchers and amplifiers, for different wavelength (1030nm, 1020nm, 995nm).

Relevant References:
[1] L. E. Zapata et al., Joule-class 500 Hz cryogenic Yb:YAG Chirped Pulse Amplifier, 2019 Conference on Lasers and Electro-Optics Europe and European Quantum Electronics Conference, OSA Technical Digest (Optical Society of America, 2019), paper ca_8_1.
[2] U. Demirbas et al., 20-mJ, sub-ps pulses at up to 70 W average power from a cryogenic Yb:YLF regenerative amplifier, Opt. Express 28, 2466-2479 (2020)
[3] H. Cankaya et al., 190-mJ cryogenically-cooled Yb:YLF amplifier system at 1019.7 nm, OSA Continuum 2, 3547-3553 (2019)
[4] U. Demirbas et al., High-power passively mode-locked cryogenic Yb:YLF laser, Opt. Lett. 45, 2050-2053 (2020)