3782
OPTICS LETTERS / Vol. 39, No. 13 / July 1, 2014
Ultra-broadband fiber optical parametric amplifier pumped by chirped pulses Damien Bigourd,1,* Patrick Beaure d’Augerès,2 Jérôme Dubertrand,2 Emmanuel Hugonnot,2 and Arnaud Mussot1 1
2
CNRS-Université Lille 1, PhLAM/IRCICA USR 3380/UMR 8523, F-59655 Villeneuve d’Ascq Cedex, France Commissariat à l’Énergie Atomique et aux Énergies Alternatives, Centre d’Etudes Scientifiques et Techniques d’Aquitaine, 15 avenue des Sablières, CS 60001, 33116 Le Barp Cedex, France *Corresponding author: damien.bigourd@univ‑lille1.fr Received April 4, 2014; revised May 13, 2014; accepted May 21, 2014; posted May 23, 2014 (Doc. ID 209394); published June 19, 2014 We numerically and experimentally demonstrate ultra-broadband fiber optical parametric amplification in a microstructured fiber pumped by stretched short pulses. The chirped pump pulse induces a temporally spread spectral gain suitable for optical parametric chirped pulse amplification in fibers. Numerical simulation shows ∼45 dB flat gain with more than 70 nm bandwidth, allowing sub-35 fs pulse amplification around 1 μm with reduced gain narrowing. This amplification principle is experimentally confirmed by measuring the instantaneous spectral gain band and related chirp. © 2014 Optical Society of America OCIS codes: (140.3490) Lasers, distributed-feedback; (190.4410) Nonlinear optics, parametric processes; (190.4380) Nonlinear optics, four-wave mixing; (060.4370) Nonlinear optics, fibers. http://dx.doi.org/10.1364/OL.39.003782
Optical parametric chirped pulse amplification (OPCPA) is now a well-established technique for high power amplification [1]. Its performances have progressively evolved toward high energy, ultra-broadband amplification, high temporal contrast, and high repetition rate mainly for advanced laser-matter interaction experiments [2,3]. For example, sub-10 fs pulse has been amplified at 100 mJ level [4] and at very high repetition rate, i.e., >100 kHz by using fiber or thin-disk-based pump amplifiers [5,6]. One exciting direction is also to amplify a single-cycle pulse and even to synthesize a subcycle pulse by carefully controlling phase and amplitude in several complex OPCPA stages [7]. Recently, Fiber-based OPCPA (FOPCPA) has been numerically [8,9] and experimentally investigated [10–13] in order to replace bulk nonlinear crystal by optical fiber. The basic principle of operation relies on a degenerate phase-matched fourwave mixing process involving one strong narrow bandwidth pump-wave, a weak stretched signal seeding the amplifier, and a generated idler wave [14]. The amplified stretched signal is then recompressed close to the Fourier transform limited pulse duration, as no spurious phase should be generated during the amplification process. In order to reach an ultrashort pulse (
OPTICS LETTERS / Vol. 39, No. 13 / July 1, 2014
Ultra-broadband fiber optical parametric amplifier pumped by chirped pulses Damien Bigourd,1,* Patrick Beaure d’Augerès,2 Jérôme Dubertrand,2 Emmanuel Hugonnot,2 and Arnaud Mussot1 1
2
CNRS-Université Lille 1, PhLAM/IRCICA USR 3380/UMR 8523, F-59655 Villeneuve d’Ascq Cedex, France Commissariat à l’Énergie Atomique et aux Énergies Alternatives, Centre d’Etudes Scientifiques et Techniques d’Aquitaine, 15 avenue des Sablières, CS 60001, 33116 Le Barp Cedex, France *Corresponding author: damien.bigourd@univ‑lille1.fr Received April 4, 2014; revised May 13, 2014; accepted May 21, 2014; posted May 23, 2014 (Doc. ID 209394); published June 19, 2014 We numerically and experimentally demonstrate ultra-broadband fiber optical parametric amplification in a microstructured fiber pumped by stretched short pulses. The chirped pump pulse induces a temporally spread spectral gain suitable for optical parametric chirped pulse amplification in fibers. Numerical simulation shows ∼45 dB flat gain with more than 70 nm bandwidth, allowing sub-35 fs pulse amplification around 1 μm with reduced gain narrowing. This amplification principle is experimentally confirmed by measuring the instantaneous spectral gain band and related chirp. © 2014 Optical Society of America OCIS codes: (140.3490) Lasers, distributed-feedback; (190.4410) Nonlinear optics, parametric processes; (190.4380) Nonlinear optics, four-wave mixing; (060.4370) Nonlinear optics, fibers. http://dx.doi.org/10.1364/OL.39.003782
Optical parametric chirped pulse amplification (OPCPA) is now a well-established technique for high power amplification [1]. Its performances have progressively evolved toward high energy, ultra-broadband amplification, high temporal contrast, and high repetition rate mainly for advanced laser-matter interaction experiments [2,3]. For example, sub-10 fs pulse has been amplified at 100 mJ level [4] and at very high repetition rate, i.e., >100 kHz by using fiber or thin-disk-based pump amplifiers [5,6]. One exciting direction is also to amplify a single-cycle pulse and even to synthesize a subcycle pulse by carefully controlling phase and amplitude in several complex OPCPA stages [7]. Recently, Fiber-based OPCPA (FOPCPA) has been numerically [8,9] and experimentally investigated [10–13] in order to replace bulk nonlinear crystal by optical fiber. The basic principle of operation relies on a degenerate phase-matched fourwave mixing process involving one strong narrow bandwidth pump-wave, a weak stretched signal seeding the amplifier, and a generated idler wave [14]. The amplified stretched signal is then recompressed close to the Fourier transform limited pulse duration, as no spurious phase should be generated during the amplification process. In order to reach an ultrashort pulse (
