Highly efficient, high average power, narrowband, pump-tunable BWOPO

Kjell Martin Mølster (1) , Marie Guionie (2) , Patrick Mutter (1) , Antoine Zheng (2) , Jean-Baptiste Dherbecourt (2) , Jean-Michel Melkonian (2) , Xavier Délen (3) , Andrius Zukauskas (1) , Fredrik Laurell (1) , Patrick Georges (3) , Myriam Raybaut (2) , Antoine Godard (4) , Valdas Pasiskevicius (1)

1 KTH - KTH Royal Institute of Technology [Kista]
2 DPHY, ONERA, Université Paris Saclay [Palaiseau]
3 Laboratoire Charles Fabry / Lasers
4 ONERA, Université Paris Saclay [Palaiseau]

We demonstrate a continuously tunable mid-infrared source that produces narrowband radiation at 1981 nm and 2145 nm based on a tunable Yb-based hybrid MOPA pump and a backward-wave optical parametric oscillator (BWOPO). The BWOPO employs a PPRKTP crystal with 580 nm domain periodicity. The BWOPO has a record-low oscillation threshold of 19.2 MW/cm2 and generates mJ level output with an overall efficiency exceeding 70%, reaching an average power of 5.65W at the repetition rate of 5 kHz. The system is mechanically robust and optical cavity-free, making it suitable for spectroscopic systems on mobile platforms. The mid-infrared signal frequency is tuned by pump tuning with a linear pump-to-signal frequency translation rate close to the predicted 1 to 1.001 Hz/Hz.

Domaines: Optique [physics.optics]

Kjell Martin Mølster, Marie Guionie, Patrick Mutter, Antoine Zheng, Jean-Baptiste Dherbecourt, et al.. Highly efficient, high average power, narrowband, pump-tunable BWOPO. Optics Letters, 2023, 48 (24), pp.6484-6487. ⟨10.1364/OL.506647⟩. ⟨hal-04435015⟩