Stabilizing the carrier envelope phase (CEP) of highly amplified titanium-sapphire lasers is one of our team’s main R&D focuses; we have been conducting experimental work with Amplitude-Technologies at IMPULSE since 2009.
In particular, we proposed an innovative device for controlling CEP fluctuations [O. Gobert et al., Opt. Express 19, 5410–5418 (2011)]. This simple, inexpensive, and compact device is based on the use of the linear electro-optic effect in a bulk material (e.g., LiNbO3 or RTP): under the action of an electric field applied to the crystal, the phase and group velocities of the laser pulses propagating through the crystal are modified independently, allowing for fine adjustment of the CEP.
This device was tested at IMPULSE. The measurements, which are in very good agreement with theoretical predictions, show a variation in the CEP of approximately 1 radian for a voltage of 300 V applied to the crystal (LiNbO₃, 4 m long and 4 mm thick) [J.-F. Hergott et al., Opt. Express 19, 19935–19941 (2011)]. This method led to a CEA–Amplitude Technologies patent [O. Gobert et al., Patent FR2969841 (2010)].
We have also developed a CEP drift measurement system that is now marketed by Amplitude Technologies. This system, based on f-2f interferometry, uses a fully analog loop to measure and correct CEP fluctuations. Using such a loop, we stabilized the CEP of a 5W, 10kHz, 23 fs TiS laser and achieved a residual noise of 200 mrad over several hours [Golinelli et al., Opt. Lett. 42 (12), 232925 (2017)]. This result, one of the best for this type of laser to our knowledge, approaches the performance of passively stabilized OPCPA systems.
References :
- Original Ti:Sa 10 kHz front-end design delivering 17 fs, 170 mrad CEP stabilized pulses up to 5 W
A Golinelli, X. Chen, E. Gontier, B. Bussière, Olivier Tcherbakoff, M. Natile, Pascal d’’Oliveira, Pierre-Mary Paul, Jean-Francois Hergott,Optics Letters. 42 (2017) 2326-2329. - Complete analog control of the carrier-envelope-phase of a high-power laser amplifier
C. Feng, J.-F. Hergott, P.-M. Paul, X. Chen, O. Tcherbakoff, M. Comte, O. Gobert, M. Reduzzi, F. Calegari, C. Manzoni, M. Nisoli, and G. Sansone, Optics Express 21 (21) (2013)25248-25256 - Carrier-envelope phase control using linear electro-optic effect,
O. Gobert, P. M. Paul, J. F. Hergott, O. Tcherbakoff, F. Lepetit, P. d’Oliveira, F. Viala, and M. Comte, Opt. Express 19 (2011) 5410–5418. - Carrier-envelope phase stabilization of a 20 w, grating based, chirped-pulse amplified laser, using electro-optic effect in a LiNbO3 crystal,
J. F. Hergott, O. Tcherbakoff, P. M. Paul, P. Demengeot, M. Perdrix, F. Lepetit, D. Garzella, D. Guillaumet, M. Comte, P. D. Oliveira, and O. Gobert, Opt. Express 19 (2011) 19935–19941 - Laser impulsionnel femtoseconde stabilise et procédé de stabilisation
brevet CEA – Amplitude Technologies
Olivier Gobert, Michel Comte, Pierre Mary Paul, Jean Francois Hergott Brevet FR2969841 (2010).