Synchronously Pumped Picosecond Optical Parametric Oscillator Tunable from 1.2 to 22 Ám a

featuring: 1.8 cm-1 linewidth and 11 ps pulse duration

above 20 mW at 5 Ám b

Integration of the OPO in an infrared-visible sum-frequency generation spectrometer with outstanding sensitivity and resolution

OPO Performances

Fig. 1. Upper right: S Scheme of the SP-OPO built around LiNbO3, KTP, AgGaSe2 and CdSe crystal. Upper center: comparison of the atmospheric absorption spectra measured by scanning by scanning the OPO beam frequency by 0.1 cm-1 steps or using a FFT infrared spectrometer with resolution set to 1 cm-1 and 2 cm-1 respectively. Upper left: Autocorrelation profile of the infrared pulses (7 Ám). Lower right: typical power ouptut in the far IR. Lower center: laser linewidths as measured by a 1 cm-1 resolution dispersive monochromator. Lower right: conversion efficiency of the AgGaS2OPO.

The scheme of a synchronously pumped picosecond Optical Parametric Oscillator (OPO) requires only one pump beam at fixed frequency to produce the desired tunable infrared from 1.2 to 10 Ám. In comparison with conventional Optical Parametric Generator/Amplifier configurations, the reduced number of conversion steps allows higher overall conversion efficiency to be achieved while the limited number of optical components means increased reliability and cost-effectiveness.

- Excellent TEM 00 mode quality and pointing stability are guaranteed by more than one meter long OPO cavity and stringent mode selection by small diameter gain-guided-amplifying medium in the non-linear crystal. Wavefront quality is preserved by avoiding the use of non-flat optics such as gratings.

- The 0.3 Ásc long bunches of picosecond pulses (pulse separation ~ 10 nsc) are generated at 25 Hzc allowing easy synchronous detection in spectroscopic applications. The energy per pulse at 5 Ám is > 20 ÁJc.

- Bunch to bunch energy stability is guaranteed by pumping the OPO well above the oscillation threshold.

- A proprietary pumping design limits the degradation of the nonlinear crystal faces, an effect intrinsic to AgGaS2b. At a bunch repetition rate of 25 Hz, an operation time in excess of 15000 hours allows more than 15 104 J of energy at 5 Ám to be generated (8 hours a day, 5 days a week of continuous operation at 25 Hz during 12 months), before the crystal faces need repair.

The OPO is operated via a PC-based user-friendly interface allowing self-calibration and self-control of the laser performances. Frequency accuracy = 0.15 cm-1, resetability = 0.1 cm-1. The interface is equipped with gated integrators for synchronous detection of analog signals to allow immediate spectroscopic applications.

Please contact us for options such as extension of the tuneability range in the visible-UV, high energy single pulse operation in the infrared (100 ÁJ/pulse at 5 Ám), high power (>300 mW infrared power generation in the near infrared from 2.5 to 4 Ám), etc.

Thanks to close partnership with the laboratories a which have developed and operated the laser since 1996, LaserSpec can provide your team with the most reliable and convivial OPO system.

a The laser system was initially developed in the research group headed by A. Tadjeddine at LURE (Orsay, France). The scientist in charge of the project was A. Peremans. The first prototype has been operating since 1996. The development of a user-friendly interface and the integration of the OPO in a SFG spectrometer is being carried out at the LLS laboratory (University of Namur, Belgium).

b The OPO can be built around a cheaper LiNbO3 crystal at the cost of a limited tuneability range from 1.5 to 4 Ám.

c Please contact us for custom designed specifications

Selected publications of scientific works using this laser.

"Vibrational spectroscopy of the C60 and K-doped C60 on Ag(111) by sum-frequency generation.",
. Caudano, A. Peremans, P.A. Thiry, P. Dumas, and A. Tadjeddine,
áJournal of Physics B: Atomic and Molecular and Optical Physics 29, 1-9 (1996).

"Dynamical charge transfer at an Interface: K doping of C60/Ag(111)."
A. Peremans, Y. Caudano, P.A. Thiry, P. Dumas, W.Q. Zheng, A. Le Rille, and A. Tadjeddine,
Physical Review Letters 78 (15), 2999-3002 (1997).

"Vibrational spectroscopy of Au(hkl)-electrolyte interface by in situ visible-infrared difference frequency generation.",
A. Le Rille, A. Tadjeddine, W. Q. Zheng, and A. Peremans,
Chemical Physics Letters, Chemical Physics Letters 271, 95-100 (1997).

"Vibrational mode and medium dependences of the infrared induced isomerization efficiency for CH2 D-CH2 D isolated in rare gas matrices",
P. Roubin,  S. Varin, P. Verlaque, S. Coussan, J.-M. Berset, J.-M. OrtÚga, A. Peremans, W.-Q. Zheng,
Journal of Chemical Physics 107, 7800-7808 (1997).

"Infrared induced interconversion between five conformers of methanol dimers trapped in nitrogen matrix.",
S. Coussan, A. Loutellier, J.P. Perchard, S. Racine, A. Peremans, A. Tadjeddine, and W.Q. Zheng,
Journal of Chemical Physics 223, 279 (1997).

"Hydrogen-bonded bridges in complexes of o-cyanophenol: Laser-induced fluorescence and IR/UV double-resonance studies",
Broquier M, Lahmani F, Zehnacker-Rentien A, Brenner V, Millie P, and Peremans A,
Journal of Physical Chemistry A 105 (28), 6841-6850 (2001).

Potential dependent organization of water at the electrified metal-liquid interface.
Schultz ZD, Shaw SK, Gewirth AA,
J Am Chem Soc. 2005 Nov 16;127(45):15916-22.

Infrared-visible sum frequency generation investigation of Cu corrosion inhibition with benzotriazole.
úSchultz ZD, Biggin ME, White JO, Gewirth AA.
Anal Chem. 2004 Feb 1;76(3):604-9.

"Cu Corrosion Inhibition by Benzotriazole Studied by Sum Frequency Generation,"
Z. D. Schultz, M. E. Biggin, J. O. White, A. A. Gewirth,
Anal. Chem., 76, 604-609 (2004).

"Formation of Ordered Multilayers from Polyoxometalates and Ag on Electrode Surfaces,"
áJ. Kim, L. Lee, B. K. Niece, J. X. Wang, A. A. Gewirth,
J. Phys.Chem. B, 108, 7927-7933 (2004).