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Light source design and development

Infrared fluorescence in a diode-pumped Yb:KYW crystal.

Solid state lasers

Historically we have done work on compact diode-pumped solid-state lasers with integrated functionality. This is involves various Nd-lasers with intra-cavity frequency doubling or Q-switched and narrow linewidth tunable Er-laser. We also developed the micro-bench concept for compact alignment- free laser construction together with Acreo AB. More recently we have worked with volume Bragg grating locked lasers and efficient lasers based on KGW and KYW. Tunable, polarized, low noise, narrow linewidth Ytterbium bulk and fiber laser have been constructed . In the prior case with an output power exceeding 100 W. In this program we are also looking into novel laser materials, which can be functionalized in several ways, for instance by employing nonlinear properties such as self-frequency doubling and self-Raman shifting.

Parametric light sources

We have an extensive program on parametric devices using periodically poled crystals, including everything from compact ns OPO to widely tunable narrow linewidth devices. Important results have also been obtained with extremely broadband picosecond and femtosecond parametric amplifiers covering the near- and mid-infrared spectral regions, with particularly interesting applications in the biomedical field.

Green pumped VBG ring-OPO to generate 760 nm signal.

Another research line is devoted to linewidth narrowed OPOs using a volume Bragg grating (VBG) as one of the mirrors. Up to 200-times reduction in linewidth has been obtained at degeneracy without any loss in power relative to a conventional OPO.

Work on cascaded nonlinear processes and cascaded parametric devices are important for extended functionality and spectral reach for nonlinear optical sources. In particular this concerns the work on coherent radiation in the mid-infrared and terahertz spectral regions, strategically important for security applications.

Ultra-broadband OPG in PPKTP to MIR followed by un-phasematched SFG.
Green pumped VBG ring-OPO to generate 760 nm signal.