Search results for "Lithium Niobate"
showing 10 items of 78 documents
GENERAZIONE DI SECONDA ARMONICA RETRO-PROPAGANTE IN NIOBATO DI LITIO CON POLING PERIODICO
2010
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.
Guided-wave frequency doubling in surface periodically poled lithium niobate: competing effects
2007
We carried out second-harmonic generation in quasi-phase-matched ? -phase lithium niobate channel waveguides realized by proton exchange and surface periodic poling. Owing to a limited ferroelectric domain depth, we could observe the interplay between second-harmonic generation and self-phase modulation due to cascading and cubic effects, resulting in a nonlinear resonance shift. Data reduction allowed us to evaluate both the quadratic nonlinearity in the near infrared as well as the depth of the uninverted domains. © 2007 Optical
Continuous-Wave Backward Frequency Doubling in Periodically Poled Lithium Niobate
2010
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.
Optical properties of Cr3+ and Ni2+ ions in MgO, LiNbO3 and LMA
1995
Abstract The electronic structures of Co2+ and Ni2+ ions are obtained by the molecular orbital LCGTO-LSD method. Electrostatic matrix calculations are performed for d3 and d8 configurations. Theoretical optical data are discussed in function of the impurity site location in the crystal cell.
Radiation displacement defect formation in some complex oxide crystals
2000
The work is devoted to an analysis of the formation processes of radiation displacement defects (RDDs) and color centers (CCs) under irradiation of complex oxide crystals. The results of the displacement process simulation as well as the analysis of the RDDs and CCs accumulation kinetics in some complex oxide crystals are presented. New experimental results on additional absorption spectra induced by neutron irradiation of LiNbO3 (LNO) crystals doped with Fe and Cr and YAlO3 (YAP) crystals doped with Nd and Er as well are presented. Dose dependencies are compared and their peculiarities are discussed. ” 2000 Elsevier Science B.V. All rights reserved.
Induced optical absorption and ITS relaxation in LiNbO3
1999
Abstract Electron pulse induced absorption spectra and their decay kinetics have been investigated in LiNbO3 crystals with various Li/Nb ratios rasnging from congruent to stoichiometric composition. It is shown that the absorption spectra, the optical density and the decay kinetics depend on the Li/Nb ratio. The rising front of the induced absorption is too fast to be resolved. The room temperature decay, characterized by the half-lifetime Δt, is faster in the stoichiometric crystal (∼ 750 ns) than in the congrruent crystal (∼ 3.5 μs).
Backward frequency doubling of near infrared picosecond pulses.
2014
We report on backward second-harmonic generation using ps laser pulses in congruent lithium niobate with 3.2 µm periodic poling. Three resonant peaks were measured between 1530 and 1730 nm, corresponding to 16th, 17th and 18th quasi-phase-matching orders in the backward configuration, with a conversion efficiency of 4.75 x 10(-5%)/W for the 16th order. We could also discriminate the contributions from inverted domains randomized in duty-cycle.
Parametric Solitons in Two-Dimensional Lattices of Purely Nonlinear Origin
2008
We demonstrate spatial solitons via twin-beam second-harmonic generation in hexagonal lattices realized by poling lithium niobate planar waveguides. These simultons can be steered by acting on power, direction, and wavelength of the fundamental frequency input.
Vibrational Analysis of Paraelectric–Ferroelectric Transition of LiNbO3: An Ab-Initio Quantum Mechanical Treatment
2021
FSG acknowledges the CINECA award under the ISCRA initiative (HP10BJO47B) for the availability of high-performance computing resources and support.
Multi-line NIR-RGB emission in Nd:LiNbO3 RPE optical waveguides
2007
Simultaneous generation of four spectral emission lines has been achieved in Nd-doped lithium niobate reverse proton exchange optical waveguide cavities. Using a pump at 800 nm, the four lines were found and they are due to lasing at 1.3735 combined with parametric conversion at 0.687, 0.574 and 0.4 mum.