NEAR INFRARED PICOSECOND PULSED BACKWARD SECOND-HARMONIC-GENERATION IN PERIODICALLY-POLED LITHIUM NIOBATE

We report on backward second-harmonic-generation in bulk periodically-poled congruent lithium niobate with a 3.2μm period. A picosecond pulsed laser allowed us exciting a resonance at 1722nm. The resonances were also resolved by temperature tuning.

Generazione di Seconda Armonica per Quasi-Phase-Matching Random in Tantalato di Litio con Poling Periodico

We experimentally observed and explained bulk Second Harmonic Generation via Random Quasi-Phase-Matching, derived from a periodically poled Lithium Tantalate sample with a randomly patterned mark-to-space-ratio.

Backward second-harmonic generation of near infrared picosecond pulses

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.

Generazione di seconda armonica per quasi accordo di fase in guide a canale su LiNbO3 periodicamente polato in superficie.

Effetti trasversi nella propagazione di fasci ottici in vetri ad alto indice

We investigate beam propagation in a novel Heavy Metal Oxide glass, reporting near infrared beam self-confinement and solitons, filamentation, interactions and conical emission at picoseconds and discussing them with the aid of a model.

All-Optical frequency Shifter in a Periodically Poled Lithium Tantalate Waveguide

A frequency shifting device is fabricated and tested in a congruent Lithium Tantalate waveguide. Periodic poling for quasi-phase-matching and channels for operation in the near-infrared C-band were obtained, demonstrating a two-stage parametric conversion.

Continuous-Wave Backward Frequency Doubling in Periodically Poled Lithium Niobate

We report on backward second-harmonic- generation in periodically poled lithium niobate with a 3.2 micron QPM period. A tunable continuous-wave Ti:Sapphire laser allowed us exciting two resonant orders. Experimental data compared well with standard theory.

AUTOFOCALIZZAZIONE VIA RANDOM QUASI-PHASE-MATCHING IN GUIDE D’ONDA DI TANTALATO di LITIO

We observe self-localization of light beams via second harmonic generation in a quasi-phase-matched proton-exchanged Lithium Tantalate slab waveguide in the presence of a random component of the periodically-poled grating.

MAPPATURA DEL DISORDINE NON LINEARE MEDIANTE INTERAZIONE PARAMETRICA A TRE ONDE

We introduce a simple approach for characterizing the ferroelectric domain distribution in bulk quadratic crystals. The approach is demonstrated in a lithium tantalate sample with periodic electric field poling and random mark-to-space ratio.

GENERAZIONE DI SECONDA ARMONICA RETRO-PROPAGANTE IN NIOBATO DI LITIO CON POLING PERIODICO

We report on backward second-harmonic-generation in bulk periodically poled congruent lithium niobate with a 3.2 micron period. A tunable continuous-wave Ti:Sapphire laser allowed us exciting two resonant quasi-phase-matched orders. Resonances were also resolved by temperature tuning.

Nonlinear Disorder Mapping Via Three-Wave Mixing in Quadratic Crystals

Fine tuning of a photonic band-gap with picosecond laser pulses

We report on light-driven tuning of the optical properties of colloidal photonic crystals (polystyrene opals) doped with gold nanoparticles (Au-np). Using picosecond pulses at 532 nm we obtained permanent changes in the stop band around 1700 nm, with resonance blue shifts as large as 30 nm.

Backward Frequency Doubling in Periodically Poled Lithium Niobate in the Pulsed Regime

Spatial Simultons in 2D Photonic Crystals of Nonlinear Origin

We observed for the very first time quadratic spatial solitons (simultons) in a two dimensional photonic lattice defined by periodic sign inversion of its susceptibilty. This is the first demonstration of quadratic self-confinement in a 2D purely nonlinear photonic crystal.