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Department of Physics

Dr. François Légaré
Institut National de la Recherche Scientifique, EMT Center
Francois Legare
Frequency domain Nonlinear Optics & Applications

102 Cardwell Hall
March 12, 2018
4:15 p.m. 

Over the recent years, we have introduced the concept of Frequency domain Optical Parametric Amplification (FOPA) [1,2]. Using this approach at the Advanced Laser Light Source (ALLS), we have developed a high energy infrared laser system delivering two-cycle 1.8 micron pulses with up to 30 mJ of energy, corresponding to 2.5 TW peak power [3]. This laser system paves the way for high flux water window soft X-ray pulses, high-field THz pulses, and high brightness ultrashort electron bunches. Among various applications of these sources, we are working to combine THz and soft X-ray pulses for probing ultrafast dynamics in solids including femtosecond magnetization dynamics and ultrafast phase transition. Furthermore, we are planning to upscale FOPA to peak power of 10 TW and current laser Ytterbium laser technologies [4] allow to dream making this laser operating at kHz repetition rate for merging high peak and high average power. By combining these technological advances, we are now working to commercialize the FOPA through a recently founded spin-off company few-cycle Inc.

While the concept of Frequency domain Nonlinear Optics has been introduced with FOPA, we have recently generalized this approach to other nonlinear optical processes. Specific results on second harmonic generation will be presented, including the linear transfer of spectral phase from the fundamental to its second harmonic, and pulse shaping in the deep UV spectral range [5].


[1] B. E. Schmidt, N. Thiré, M. Boivin, A. Laramée, F. Poitras, G. Lebrun, T. Ozaki, H. Ibrahim, and F. Légaré, "Frequency domain optical parametric amplification," Nature Commun. 5, 3643 (2014).

[2] P. Lassonde, N. Thiré, L. Arissian, G. Ernotte, F. Poitras, T. Ozaki, A. Laramée, M. Boivin, H. Ibrahim, F. Légaré, B. E. Schmidt, "High gain Frequency domain Optical Parametric Amplification," IEEE J. Sel. Top. Quant. Electr. 21, 8700410 (2015).

[3] V. Gruson, G. Ernotte, P. Lassonde, A. Laramée, M. Bionta, M. Chaker, L. Di Mauro, P. Corkum, H. Ibrahim, B. Schmidt, and F. Legaré, "2.5 TW, two-cycle IR laser pulses via frequency domain optical parametric amplification," Opt. Express 25, 27706-27714 (2017).

[4] C. Baumgarten, M. Pedicone, H. Bravo, H. Wang, L. Yin, C. Menoni, J. Rocca, and B. Reagan, "1  J, 0.5  kHz repetition rate picosecond laser," Opt. Lett. 41, 3339-3342 (2016).

[5] B. E. Schmidt, P. Lassonde, G. Ernotte, M. Clerici, R. Morandotti, H. Ibrahim, and F. Légaré, " Decoupling Frequencies, Amplitudes and Phases in Nonlinear Optics," Scient. Rep. 7, 7861 (2017).