Abstract Laser cladding is a new surface repair method that can improve the wear and corrosion resistance of substrate surfaces. However, layer typically exhibits rough surface, high hardness large residual tensile stress, thus requires further machining finishing. Ultrasonic rolling (U-rolling) highly efficient finishing strengthening process combines ultrasonic technology with traditional (T-...

This communication describes a long (1 cm), laser-pumped, liquid core-liquid cladding (L2) waveguide laser. This device provides a simple, high intensity, tunable light source for microfludic applications. Using a core solution of 2 mM rhodamine 640 perchlorate, optically pumped by a frequency-doubled Nd:YAG laser, we found that the threshold for lasing was as low as 22 muJ (16-ns pulse length)...

Cracking of nickel superalloys with a high content γ’-phase remains an unresolved problem, including in technologies for repairing gas turbine engines blades. Laser cladding is method material deposition used to repair parts exposed aggressive environment and surface wear. Cladding parameters have influence on cracking susceptibility superalloys. Alloy ZhS32 has propensity hot when laser radiat...

A theoretical model for laser cooled continuous-wave fiber amplifier is presented. The amplification process takes place in the Tm 3+ -doped core of the fluoride ZBLAN (ZrF4-BaF2LaF3-AlF3-NaF) glass fiber. The cooling process takes place in the Yb 3+ :ZBLAN fiber cladding. It is shown that for each value of the pump power and the amplified signal there is a distribution of the concentration of ...

We report stable, passive, continuous-wave (CW) mode-locking of a compact diode-pumped waveguide Nd:YAG laser with a single-layer graphene saturable absorber. The depressed cladding waveguide in the Nd:YAG crystal is fabricated with an ultrafast laser inscription method. The saturable absorber is formed by direct deposition of CVD single-layer graphene on the output coupler. The few millimeter-...

A high-power diode-cladding-pumped Ho³⁺-doped fluoride glass fiber laser operating in cascade mode is demonstrated. The ⁵I₆→⁵I₇ and ⁵I₇→⁵I₈ laser transitions produced 0.77 W at a measured slope efficiency of 12.4% and 0.24 W at a measured slope efficiency of 5.2%, respectively. Using a long fiber length, which forced a large threshold for the ⁵I₇→⁵I₈ transition, a wavelength of 3.002 μm was mea...

We study numerically depressed-index cladding, buried, micro-structured optical waveguides that can be formed in a lithium niobate crystal by femtosecond laser writing. We demonstrate to which extent the waveguiding properties can be controlled by the waveguide geometry at the relatively moderate induced refractive index contrasts that are typical of the direct femtosecond inscription.

We demonstrate a high-power cladding-pumped Er-Yb codoped fiber laser with 74% efficiency. A pump-limited output power of 264 W is obtained using in-band pumping at 1535 nm. We compare the efficiency of 1480 and 1535 nm pumping through numerical simulations and experimental measurements.

We introduce a femtosecond-laser-based technique for selective opening of airholes in photonic crystal fibers (PCFs). With this technique, selective filling and inflation of the airholes in the PCF cladding are demonstrated. The technique may find important applications in tailoring or altering PCF characteristics and make it possible to seamlessly integrate various components/functions into PCFs.

Strong waveguide Bragg-gratings (10 dB reflectivity) were fabricated by the directwrite technique in ZBLAN glass. Based on a depressed cladding, an array of 169 periodic and in phase modifications was placed inside the core. OCIS codes: (230.7370) Optical devices: Waveguides; (230.1480) Bragg reflectors; (350.3390) Laser materials processing