Search results for " Parametric processes"
showing 3 items of 3 documents
Parametric self-trapping in the presence of randomized quasi phase matching
2010
We report on experimental evidence of parametric spatial solitons in a quadratic crystal with randomized periodic ferroelectric poling. Two-color self-focusing via quadratic cascading overcomes the diffractive nature of both fundamental and frequency-doubled beams.
Backward second-harmonic generation of near infrared picosecond pulses
2014
We report on backward second-harmonic generation using picosecond laser pulses in congruent lithium niobate with 3.2 µm periodic poling. By tuning both the pump wavelength and the sample temperature, we observed three resonant peaks in the range 1530-1730 nm, corresponding to 16th, 17th and 18th quasi-phase-matching orders, respectively. A maximum conversion efficiency of 0.475% was achieved at the 16th order with a 10 kW peak pump power. The latter is the highest conversion reported in bulk to date, for the backward configuration, with an improvement greater than 50% with respect to those previously achieved with nanosecond pulses for the same order of resonance.
Continuous-wave backward frequency doubling in periodically poled lithium niobate
2010
We report on backward second-harmonic-generation in bulk periodically poled congruent lithium niobate with a 3.2 microns period. A tunable continuous-wave Ti:sapphire laser allowed us exciting two resonant quasi-phase-matching orders in the backward configuration. The resonances were also resolved by temperature tuning and interpolated with standard theory to extract relevant information on the sample.