Elodie Boursier

Angle noncritical phase-matched second-harmonic generation in the monoclinic crystal BaGa 4 Se 7

We performed a complete study of angle noncritical phase-matched second-harmonic generation in BaGa4Se7 in the mid-infrared region. We measured the dielectric frame orientation and showed that it does not rotate as a function of wavelength. We determined the phase-matching wavelengths and the associated spectral and angular acceptances along the x and y axes of the dielectric frame. We also estimated the magnitude of the nonlinear coefficients involved.

Phase-matching directions and refined Sellmeier equations of the monoclinic acentric crystal BaGa 4 Se 7

We directly measured the phase-matching directions of second-harmonic and difference frequency generation in the principal planes of the biaxial BaGa4Se7 (BGSe) crystal using the sphere method. The simultaneous fit of the data allowed us to refine the Sellmeier equations of the three principal refractive indices of BGSe, and to calculate the tuning curves for infrared optical parametric generation.

Study of difference frequency generation and optical parametric amplification in La 3 Ga 5.5 Ta 0.5 O 14 in the femtosecond regime

Optical parametric generation in nonlinear crystals across the atmosphere transmission band II (3–5 μm) is of interest for various applications such as infrared spectroscopy or countermeasures. For an efficient parametric generation in this spectral range with well-developed ultrashort laser sources, we identified Langatate La<inf>3</inf>Ga<inf>5.5</inf>Ta<inf>0.5</inf>O<inf>14</inf> (LGT) [1]. LGT is transparent from 0.25 up to 6.5 μm and can be grown in large sizes using the Czochralski method. Its unique nonlinear coefficient d<inf>11</inf>=2.4 ± 0.4 pm/V at λ=0.67 μm as well as the refinement of the Sellmeier equations are reported in ref [1]. The study highlights the potential for LGT to generate broadband spectrum between 1.5 and 5 μm if pumped around 0.97 μm available from a Ti:Sapphire (Ti:Sa) laser.

Phase-Matching Measurements and Refinement of Sellmeier Equations of the New Nonlinear Crystal BaGa4Se7

We performed direct measurements of phase-matching directions of second harmonic and difference frequency generation in BaGa4Se7 (BGSe). Fitting of the data allowed us to refine the Sellmeier equations of the principal refractive indices of BGSe.

Angular noncritical phase-matched second harmonic generation in BaGa4Se7

We performed a complete study of angular noncritical phase-matched second harmonic generation in the monoclinic BaGa4Se7 (BGSe). We determined the corresponding wavelengths, conversion efficiencies and acceptances, as well as the involved nonlinear coefficients.

All-parametric dual-wavelength source for difference frequency generation experiments

A versatile DFG source based on two independent OPOs widely tunable between 1.4 and 4.25 µm is reported. It was validated with preliminary DFG experiments performed in CdSe crystals with output in the range 8 - 10 µm.