Infrared dielectric function spectra and phonon modes of high-quality, single crystalline, and highly resistive wurtzite ZnO films were obtained from infrared (300–1200 cm−1) spectroscopic ellipsometry and Raman scattering studies. The ZnO films were deposited by pulsed-laser deposition on c-plane sapphire substrates and investigated by high-resolution x-ray diffraction, high-resolution transmission electron microscopy, and Rutherford backscattering experiments. The crystal structure, phonon modes, and dielectric functions are compared to those obtained from a single-crystal ZnO bulk sample. The film ZnO phonon mode frequencies are highly consistent with those of the bulk material. A small redshift of the longitudinal optical phonon mode frequencies of the ZnO films with respect to the bulk material is observed. This is tentatively assigned to the existence of vacancy point defects within the films. Accurate long-wavelength dielectric constant limits of ZnO are obtained from the infrared ellipsometry analysis and compared with previously measured near-band-gap index-of-refraction data using the Lyddane–Sachs–Teller relation. The ZnO model dielectric function spectra will become useful for future infrared ellipsometry analysis of free-carrier parameters in complex ZnO-based heterostructures.

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We demonstrate that the growth of F16CuPc 1-D nanostructures can be directed by templates of gold nanoparticles. The growth occurs via vapor-phase transport, whereby the gold nanoparticles act as nucleation sites for F16CuPc molecules and promote their anisotropic growth. The F16CuPc 1-D structures adopt diameters of approximately 15-30 nm independent of the nanoparticle size. This approach enables a technologically simple and inexpensive fabrication of very uniform organic 1-D structures (aspect ratio of approximately 30) and precise control of their location and packing density.

Temperature-dependent dielectric and electro-optic properties of a ZnO-BaTiO3-ZnO heterostructure grown by pulsed-laser deposition on (0001) sapphire are reported. The wurtzite-structure ZnO layers serve as transparent conducting electrodes. Previously observed coupling effects within the wurtzite-perovskite heterostructure by spectroscopic electro-optic ellipsometry birefringence measurements manifest themselves as a “pinning” of the ferroelectric polarization in the BaTiO3 layer by the cladding ZnO layers. Temperature-controlled electro-optic Raman measurements assign the electro-optic birefringence results to a temperature-driven phase transition resulting from the leakage current within the sample. High-temperature small-signal capacitance measurements exploiting the conductive electrode properties of the cladding layers reveal occurrence of the Curie temperature of the BaTiO3 layer at 384 K.

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Silicon one-dimensional (Si 1D) materials are of particular relevance due to their prospect as versatile building materials for nanoelectronic devices. We report the growth of Si 1D structures from quasi-hexagonally ordered gold (Au) nanoparticle (NP) arrays on borosilicate glass (BSG) and SiOx/Si substrates. Using hydrogen instead of oxygen plasma during NP preparation enhances the catalytic activity of AuNPs (diameters of 10-20 nm), enabling Si 1D growth at temperatures as low as 320 degrees C. On BSG, Si nanowires (SiNWs) are identified and reasonable vertical alignment is achieved at 420 degrees C. On SiOx/Si, only Si nanotubes (SiNTs) are obtained right up to 420 degrees C. A mixture of SiNTs and SiNWs is observed at 450 degrees C and only SiNWs grow at 480 degrees C.

Gold‐borne: Phthalocyanine (F16CuPc) assembles into multiwalled nanotubes by vapor deposition onto SiO2 surfaces functionalized by Au nanodots. Their length can be tuned over a large range. The picture shows the wall spacing d* of a F16CuPc nanotube as deduced from the first diffraction fringe of the electron diffractogram.

Size, composition, and pattern formation are crucial elements in the fabrication of functional multicomponent nanoparticles (NPs). Self-assembly techniques provide relevant control over NP size distribution (down to a few nanometers in diameter), but more importantly, such techniques are amenable for practical applications since the resulting NPs (and arrays thereof) are programmed in the molecular structure of the precursors. Here, the diblock copolymer micelle nanolithography concept of achieving monodisperse NPs is extended to direct the synthesis of multicomponent core-shell NPs arranged in a triangular lattice. Special emphasis is set on Co(core)@Fe(shell) and corrosion resistant (FeCo)(core)@Au(shell) NPs. Electron microscopy analyses show a variety of core-shell geometries spanning a wide range of oxide, metal, and alloy combinations.