Strong high-quality fiber Bragg gratings with photoinduced refractive-index modulation of more than 10^-3 were written in a Corning SMF-28 fiber, a P₂O₅-doped-core fiber and a pure-silica-core fluorine-doped-cladding fiber by third-harmonic radiation (267 nm, 150 fs and 1.2-1.8×10¹¹ W/cm²) of a femtosecond Ti:sapphire laser using a phase mask. We compare the 267-nm photosensitivity responses with the results of irradiation by 193-nm ArF and 157-nm F₂ excimer lasers. The dependence of the refractive-index change on the exposure dose and the annealing characteristics of the fabricated gratings are typical for Type-I UV-written fiber gratings.

A narrow line distributed feedback (DFB) fiber laser based on a 16 mm long Bragg grating, inscribed in a purpose-made strongly activated and highly photosensitive silica fiber, was fabricated and tested. A fiber preform synthesized by means of surface-plasma chemical vapor deposition (SPCVD), and a standard Bragg grating writing technology using an ArF excimer laser and a $\pi$-shifted phase mask, were applied to fiber drawing and grating writing, respectively. A single-mode generation regime of the DFB laser core-pumped at a wavelength of 976 nm was obtained, the measured linewidth being less than 8 kHz.

The fabrication of photoand thermostable periodic structures from silver nanoparticles in polymer plates (cross-linked oligourethanemethacrylate impregnated with silver precursors Ag(hfac) and Ag(fod) dissolved in the supercritical carbon dioxide) is studied. The process is based on the local (depending on the irradiated spot size) photochemical decomposition of the silver precursors in the polymer matrix that initiates the atomic aggregation and creation of silver nanoparticles with the plasmon resonance in absorption in the spectral range 420–430 nm. The third-harmonic radiation of a Nd:YAG laser (355 nm) and the Kr⁺-laser (521 nm) radiation are employed for the recording of periodic structures with submillimeter and micron resolutions. The photosensitivity of the polymer matrices impregnated with the silver precursors to the UV and visible radiation is discussed.