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One-dimensional ferroelectric photonic crystals have been produced by filling porous anodic aluminum oxide with sodium nitrite. Introducing sodium nitrite into the pores of the photonic crystals has been shown to cause a 40-nm bathochromic shift in the spectral position of their bandgap. The results of this study demonstrate the feasibility of using aluminum oxide-based composite photonic crystals as narrow-band selective mirrors.

A method has been demonstrated for doping carbon nanotubes (CNTs) with nitrogen during synthesis in an acetylene + ammonia atmosphere at different temperatures in the range 550–750°C, and conditions have been found for effective nitrogen doping of CNTs depending on synthesis temperature. The concentrations of various elements in the synthesized CNTs have been determined by X-ray photoelectron spectroscopy. Raman measurements with the use of a Raman microscope have made it possible to follow variations in the relative intensities of the G and D bands as functions of nitrogen dopant concentration in the CNTs. We have detected strong Raman overtone combination satellites whose parameters depend on the structural perfection of the synthesized CNTs.

We have measured photoluminescence spectra of uranyl nitrate (UO2(NO3)2) crystals and a UO2(NO3)2-filled opal crystal. The spectra have been compared to the corresponding photoluminescence spectrum of photonic glass. The photoluminescence spectra were excited by semiconductor light-emitting diodes, a cw laser, and repetitive laser pulses. The excitation wavelengths were located in the resonance absorption band of the uranyl compound. This has offered the possibility of measuring the photoluminescence spectrum of UO2(NO3)2 at an acquisition time of 1 ms, using the smallest possible amount of the substance (down to 10–9 g). The spectra have been obtained in the range 200–1000 nm using a fiber-optic minispectrometer.

We have found conditions for high-speed measurements of Raman spectra of lithium niobate and lithium tantalate single crystals and ceramics. To measure Raman spectra, we used 180° scattering geometry and a minispectrometer equipped with an array detector. The Raman spectra obtained at two distinct orientations of the single crystals relative to the excitation beam direction have been shown to have different frequencies of transverse and longitudinal optical modes. The Raman spectra of the ceramics are mainly contributed by transverse optical modes.

This paper presents a systematic study of Raman spectra of nanocomposite photonic crystals produced using opal matrices or anodic aluminum oxide and filled with various inorganic compounds. We compare Raman spectra of the starting inorganic compounds (K2Cr2O7, CrO3, and KIO3) and nanocomposite photonic crystals whose pores are filled with the inorganic substances. Our results open up the possibility of producing high-performance sensors of inorganic substances introduced into the pores of photonic crystals, based on analysis of enhanced Raman scattering in a nanocomposite photonic crystal.

We have studied spontaneous and stimulated Raman spectra of polycrystalline LiOH and LiOD. The observed spontaneous Raman spectra contain low-frequency high-quality-factor lattice modes corresponding to translational and librational oscillations of the ions. The stimulated Raman spectrum has been found to contain several Stokes and anti-Stokes satellites with a large frequency shift.