Survey of spatio-temporal couplings throughout high-power ultrashort lasers.

The investigation of spatio-temporal couplings (STCs) of broadband light beams is becoming a key topic for the optimization as well as applications of ultrashort laser systems. This calls for accurate measurements of STCs. Yet, it is only recently that such complete spatio-temporal or spatio-spectral characterization has become possible, and it has so far mostly been implemented at the output of the laser systems, where experiments take place. In this survey, we present for the first time STC measurements at different stages of a collection of high-power ultrashort laser systems, all based on the chirped-pulse amplification (CPA) technique, but with very different output characteristics. This measurement campaign reveals spatio-temporal effects with various sources, and motivates the expanded use of STC characterization throughout CPA laser chains, as well as in a wider range of types of ultrafast laser systems. In this way knowledge will be gained not only about potential defects, but also about the fundamental dynamics and operating regimes of advanced ultrashort laser systems.

Experimental demonstration of five-beam-pumped optical parametric amplification.

We experimentally demonstrated optical parametric amplification with five pumps coming from two different oscillators. By spreading those partially mutually incoherent pumps at 532 nm over different phase-matching directions around a signal at 725 nm, we obtained a pumps-to-signal efficiency of 27%.

Dual-wavelength source from 5%MgO:PPLN cylinders for the characterization of nonlinear infrared crystals.

We conceived a unique fully parametric source based on two independent cylindrical OPOs simultaneously pumped by the same Nd:YAG laser. Each OPO delivers more than 2 mJ and is continuously tunable between 1.41 µm and 4.3 µm. This source is of particular interest for the study of the generation of infrared parametric light in nonlinear crystals. It was validated by performing difference frequency generation experiments in CdSe crystals with output in the range 8 - 10 µm.

Phase-matching loci and angular acceptance of non-collinear optical parametric amplification.

A general study of phase-matching loci and associated angular acceptances is performed in the case of non-collinear parametric amplification. Numerical and analytical calculations, as well as measurements, are described for the uniaxial BBO crystal and the biaxial LBO crystal.

Wavelength dispersion measurement of electro-optic coefficients in the range of 520 to 930 nm in rubidium titanyl phosphate using spectral interferometry.

Rubidium titanyl phosphate (RTP) is widely used for electro-optical applications at low switching voltages. RTP is nonhygroscopic and does not induce piezoelectric ringing up to the megahertz range. It has large electro-optic (EO) coefficients and a high damage threshold. We present here the EO coefficient wavelength dispersion measurements in the [550,950] nm spectral range using a method based on spectral interferometry. These data are necessary for, among other things, a quantitative modelization of an EO carrier-envelope phase shifter.