Abstract

An ultrashort mid-infrared (IR) source beyond 5 µm is crucial for a plethora of existing and emerging applications in spectroscopy, medical diagnostics, and high-field physics. Nonlinear generation of such sources from well-developed near-IR lasers, however, remains a challenge due to the limitation of mid-IR crystals. Based on oxide ${{\rm La}_3}{{\rm Ga}_{5.5}}{{\rm Nb}_{0.5}}{{\rm O}_{14}}$ (LGN) crystals, here we report the generation of femtosecond pulses tunable from 3 to 7 µm by intrapulse difference-frequency generation of 7.5 fs, 800 nm pulses. The efficiency and bandwidth dependences on pump polarization and crystal length are studied for both Type-I and Type-II phase-matching configurations. Maximum pulse energy of  ${\sim}{10}\;{\rm nJ}$ is generated at 5.2 µm with a conversion efficiency of ${\sim}{0.14}\%$. Because of the few-cycle pump pulse duration, the generated mid-IR pulses are as short as about three cycles. These results, to the best of our knowledge, represent the first experimental demonstration of LGN in generating mid-IR ultrashort pulses.

© 2020 Optical Society of America

Mid-infrared pulsed nanosecond difference frequency generation of oxide LGN crystal up to 5.7 µm

Chen Cui, Dazhi Lu, Fei Liang, Jiyang Wang, Haohai Yu, and Huaijin Zhang
Opt. Lett. 46(4) 785-788 (2021)

Efficient generation of mid-infrared few-cycle pulses by the intrapulse difference-frequency generation in YCOB

Xingbin Gu, Jinsheng Liu, Peng Yuan, Xiaoniu Tu, Dongfang Zhang, Jing Wang, Guoqiang Xie, and Jingui Ma
Opt. Lett. 47(19) 5244-5247 (2022)

Femtosecond 8.5  μm source based on intrapulse difference-frequency generation of 2.1  μm pulses

Ondřej Novák, Peter R. Krogen, Tobias Kroh, Tomáš Mocek, Franz X. Kärtner, and Kyung-Han Hong
Opt. Lett. 43(6) 1335-1338 (2018)

Few-cycle mid-infrared pulses from BaGa₂GeSe₆

Ugaitz Elu, Luke Maidment, Lenard Vamos, Tobias Steinle, Florian Haberstroh, Valentin Petrov, Valeriy Badikov, Dmitrii Badikov, and Jens Biegert
Opt. Lett. 45(13) 3813-3815 (2020)

Multi-millijoule, few-cycle 5 µm OPCPA at 1 kHz repetition rate

Lorenz von Grafenstein, Martin Bock, Dennis Ueberschaer, Esmerando Escoto, Azize Koç, Kevin Zawilski, Peter Schunemann, Uwe Griebner, and Thomas Elsaesser
Opt. Lett. 45(21) 5998-6001 (2020)