EUROPHOTON 2022

We demonstrate an agile high power Yb-fiber frequency comb laser system with long-term stable remote-controlled operation via digital feedbacks and user-friendly interfaces. A programmable, phase and amplitude filter allows optimization of the laser output pulse for driving a subsequent nonlinear process, such as nonlinear frequency shifting and XUV-comb generation.

We present here a new FROG retrieval algorithm which performs well under heavy noise conditions through a structured random search of the available input space. It can retrieve pulses from any FROG geometry, partial datasets, as well as blind FROG retrieval.

We report the very first demonstration of wavelength-tunable operation in the UV from a diode-pumped Alexandrite laser. 375-385nm continuous tuning is obtained using a high-power diode-pumped tunable Alexandrite laser and a Type I critically phase-matched BBO crystal. The use of PPLN waveguides for UV generation is also discussed.

We present a cavity-dumped Q-switched Alexandrite laser for LIDAR applications under CW double-pass diode pumping. A record pulse energy of >500 $\mu$J was achieved at 755 nm, 2.8 ns and 5 kHz. Furthermore, efficient laser operation at 10 – 20 kHz repetition rates is demonstrated for the first time.

We report a 7.5W Alexandrite (Cr-doped Chrysoberyl) ring laser operating at 757nm. Pumping is provided by a 200 𝜇m fibre-coupled red laser diode (640nm) with optical and slope efficiencies of 28% and 35%, respectively. This result shows potential for high-power single-longitudinal-mode operation across 720-800nm and 360-400nm by second-harmonic-generation.

We developed a cost-effective broadband SWIR-MIR mJ-level OPCPA pumped and seeded with 1.2 ps Yb:YAG laser. Pulses amplified to 2 mJ in the wavelength range 1900 – 2300 nm with a pump-to-signal record conversion efficiency of ~30% and compressed up to 50 fs in 3-stage OPCPA based on BiBO.

We present spectroscopic investigations and laser operation of a Czochralski-grown Tm3+:YScO3 mixed sesquioxide crystal. We observed broadband absorption and emission spectra, desirable for ultrafast 2 µm lasers. Continuous wave laser experiments were performed using a 780 nm laser diode, and a maximum slope efficiency of 40% was achieved.

Single-frequency operation of a diode-pumped praseodymium-doped YLF laser has been demonstrated using an elegant cavity design. Over 100 mW of single-frequency operation has been achieved from 687 nm to 705 nm with one cavity arrangement. This laser system targets use in neutral strontium optical clocks.