New possibilities in nonlinear frequency conversion for near and mid-IR compact sources

Thomas Godin

Ultrafast fiber lasers are now well-established alternatives to solid-state lasers in many research-oriented and industrial applications. Standard fiber laser technology, however, faces two major limitations: (i) the detrimental influence of nonlinear effects due to the strong spatial confinement of the pulses, thus limiting the energy scaling, and (ii) the limited available wavelengths due to rare-earth (RE) gain fibers, restricting the tunability of such sources.

In our group (CORIA - Univ. Rouen Normandie) we currently explore several new technologies with the purpose of reaching previously unattainable spectral regions and/or achieving efficient energy scaling in wavelength ranges where no RE-based laser is available. In this presentation, we will focus on two specific nonlinear frequency conversion techniques we recently developed:

• The new concept of fiber optical parametric chirped-pulse oscillator (FOPCPO), combining the CPA technique with the advantages of resonant fiber optical parametric oscillators (FOPOs).
• Mid-infrared optical parametric generation in the mid-IR by pumping custom-designed orientation-patterned gallium arsenide (OP-GaAs) rib waveguides using a homemade mode-locked fluoride fiber laser.

• PhD thesis at the University of Caen (France): nonlinear material characterization and laser beam shaping (co-supervision Univ. Sao Carlos, Brazil; National Laser Centre, South Africa)

• Post-doc in nonlinear fiber optics at the Institut FEMTO-ST (France): study of extreme events in supercontinuum generation
• Associate Professor at the University of Rouen Normandie, CORIA laboratory (France): innovative laser sources and ultrafast optical metrology