400 W average power Q-switched Yb:YAG thin-disk-laser.

We report on producing up to 403 W average power directly from an acousto-optically Q-switched Yb:YAG thin-disk laser (TDL). To achieve this power, it has theoretically and experimentally been shown that the laser stability border could be shifted toward higher repetition rates by engineering of the output coupler transmittance. This allows for stable operation of the laser at higher frequencies and a further increase in the power extraction from the active medium.

Effect of different surface treatments of presintered or sintered zirconia on bond strength to dentine.

Aim: To compare the effect of different zirconia surface treatments on cement bond strength to dentine.

Materials And Methods: Stick-shaped pre-sintered zirconia (N = 128) were prepared and divided into eight groups ( = 16). Three surface treatments (sandblasting, neodymium-doped yttrium aluminum garnet [Nd:YAG] or carbon dioxide laser irradiation) were applied, either before (later to be sintered) or after sintering.

Observation of spatial nonlinear self-cleaning in a few-mode step-index fiber for special distributions of initial excited modes.

In this paper, we experimentally demonstrate that a nonlinear Kerr effect in suitable coupling conditions can introduce a spatially self-cleaned output beam for a few-mode step-index fiber. The impact of the distribution of the initial excited modes on spatial beam self-cleaning has been demonstrated. It is also shown experimentally that for specific initial conditions, the output spatial pattern of the pulsed laser can be reshaped into the LP mode due to nonlinear coupling among the propagating modes.

The effect of population inversion saturation on the transverse mode instability threshold in high power fiber laser oscillators.

To achieve a 3.02 kW Yb-doped fiber laser oscillator, the behavior of transverse mode instability (TMI) is experimentally studied in different pumping configurations; co, hybrid, counter, and bidirectional. A comparative analysis showed that population inversion saturation has a substantial impact on TMI threshold enhancement in high power fiber oscillators.

Laser Ablation-Assisted Synthesis of Poly (Vinylidene Fluoride)/Au Nanocomposites: Crystalline Phase and Micromechanical Finite Element Analysis.

In this research, piezoelectric polymer nanocomposite films were produced through solution mixing of laser-synthesized Au nanoparticles in poly (vinylidene fluoride) (PVDF) matrix. Synthetization of Au nanoparticles was carried out by laser ablation in -methyle-2-pyrrolidene (NMP), and then it was added to PVDF: NMP solution with three different concentrations. Fourier transformed infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were carried out in order to study the crystalline structure of the nanocomposite films.

Outpatient Transurethral Cystolithotripsy of Large Bladder Stones by Holmium Laser.

Introduction: To assessment of the efficacy and safety of transurethral cystolithotripsy of large bladder stones by holmium laser in the outpatient setting.

Methods: In a prospective study, 48 consecutive adult patients with large bladder stones, were enrolled for transurethral cystolithotripsy. Patients older than 18 years, with bladder stones larger than 2 cm were enrolled.

All-optical flip-flop based on nonlinear effects in fiber Bragg gratings.

We demonstrate a novel design for a passive all-optical R-S flip-flop with separate set-rest ports based on nonlinearity in the fiber Bragg gratings (FBGs). The spectrum of FBGs in the presence of the Kerr effect is investigated, and cw and transient characteristics of nonlinear-induced bistability of the passive distributed feedback structures are studied by numerical solving of coupled-mode equations. It is shown that a pulse with a pulsewidth of 0.

Necklace-shaped Au-Ag nanoalloys: laser-assisted synthesis and nonlinear optical properties.

Here in this paper, necklace-shaped Au-Ag nanoalloys (NAs) have been synthesized by a laser-based approach. A chain of Ag nanoparticles (NPs), which were joined together with Au junctions, was formed upon copper vapor laser (CVL) irradiation of a colloidal mixture of Ag and Au NPs; while the corresponding NPs were separately provided by laser ablation of gold and silver targets in deionized water by a 1064 nm Q-switched Nd:YAG laser. Dependence of the NAs development process on the CVL irradiation time in three distinct stages of as-mixed, nucleation and complete formation has been systematically studied by UV-vis optical absorption spectroscopy analysis as well as by transmission electron microscopy (TEM), which was exploited to visually confirm the NAs evolution through the process.