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The first method of plasmon-induced nitroxide-mediated polymerization on periodical gold gratings has been developed.

The systematic study of structures with gold and silver nanoparticles (MeNPs) of various shapes and dielectric functions immobilized onto the silver grating is performed. The structures may serve as double resonance SERS (surface-enhanced Raman spectroscopy) systems with coupling between surface plasmon polariton (SPP) supported by the silver grating and localized surface plasmons (LSPs) excited on the grafted metal nanoparticles (MeNPs). The silver grating supports SPP excitation under the 785 nm wavelength illumination. Spherical silver and gold nanoparticles, triangular silver nanoprisms and gold nanorods are prepared and used with the aim to gradually cover the LSP excitation in the 400–850 nm wavelength range. MeNPs are grafted through the 4,4′-biphenyldithiol (BFDT) linkers. Rhodamine 6G (R6G) molecules are added onto SERS substrates and located above and between the MeNPs. Several wavelengths (470, 532, and 785 nm) are applied to probe the SERS response. Depending on the nanoparticles type and excitation wavelength a significant SERS signal is produced by R6G or BFDT molecules. Properties of the prepared structures are simulated using the Finite-difference time-domain method (FDTD). The measured and simulated SERS data are in reasonable agreement, the measured values being lower than those calculated.

Surface-enhanced Raman scattering (SERS) spectroscopy is an extremely sensitive analytical technique that is capable of identifying the vibration signatures of target molecules up to single-molecule sensitivity. In this work, the ultrahigh sensitivity of SERS has been achieved through the immobilization of sharp-edges specific nanoparticles -so-called gold multibranched NPs (AuMs) on the silver grating surface through the biphenyl dithiol. This approach allows combining the extremely high SERS enhancement factor (better than that in the case of AuMs immobilized on the flat Ag film) with perfect reproducibility of Raman signals. The grating was created on the polymer substrate using the excimer laser modification and further metal deposition and has an ''active'' area 5 Â 10 mm 2 , enabling the macroscale SERS substrate preparation. The wet-chemistry synthesized AuMs were then immobilized on the grating surface and the produced structure allows SERS measurements with a portable Raman spectrophotometer. The prepared structures were checked using the AFM, UV-Vis, and Raman spectroscopy techniques.

Micro‐sized patterns were created on thin poly(methyl methacrylate) (PMMA) films by the effect of external field, perpendicular to the film surface. The PMMA film, prepared by spin‐coating onto Si wafer, was heated to the fluid temperature (275 °C) and a linear pattern was created by the effect of electric field produced by a strip electrode. In another experiment, a round pattern was created as a result of local laser heating of the PMMA film under homogenous electrical field. The created patterns were analyzed by optical microscopy and profile meter. The dependence of the form and size of the created patterns on the intensity of the electric field, exposure time, and initial film thickness was examined. Wave guiding property of a linear pattern, produced by the above technique, was examined in a simple experiment. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1131–1135, 2009

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We demonstrated two methods of increasing the bandwidth of a broadband light source based on amplified spontaneous emission in thulium-doped fibres. Firstly, we have shown by means of a comprehensive numerical model that the full-width at half maximum of the thulium-doped fibre based broadband source can be more than doubled by using specially tailored spectral filter placed in front of the mirror in a double-pass configuration of the amplified spontaneous emission source. The broadening can be achieved with only a small expense of the output power. Secondly, we report results of the experimental thulium-doped fibre broadband source, including fibre characteristics and performance of the thulium-doped fibre in a ring laser setup. The spectrum broadening was achieved by balancing the backward amplified spontaneous emission with back-reflected forward emission.

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