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We report on the unusual phenomenon of pattern formation in the thin film of Ni+C[sub 60] mixture deposited on the MgO(100) substrate. Under certain deposition kinetics a periodic system of stripe domains was formed. The domains consist of sub-half-micrometer large droplets encompassed with a thin C[sub 60]--based rind with a possible polymeric structure. The stripes are embedded in the double-layer platform falling into the epitaxial Ni and amorphous-C (a-C) thin films. During co-deposition the C[sub 60] molecules partly disintegrate and transform towards a-C. Due to the accumulation of a-C (with limited solubility in Ni) thermodynamic instability arises in the system and reaching a certain level, it triggers spontaneous partitioning (and self-organization) of the deposited material. As a principal mechanism of the pattern formation, a sequential drift and coordinate release of the thermodynamic instability is proposed. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Elaboration of functional hybrid nanostructures integrating noble metal nanoparticles (NPs) is an attractive topic in nanoplasmonics prompting unique technologies. Here we report on remarkable plasmonic properties of the self-assembled Ag x C 60 nanocomposite (NC) films, consisting of dense 3D-assembly of small Ag NPs and supporting C 60 medium. Systematic study of optical absorption spectra allowed us to disclose the spectral peculiarities of plasmonic and molecular excitations in the Ag x C 60 NC films in the broad range of Ag concentrations, 0< x < 30. Analysis of the plasmonic modes evaluated in this study designates intriguing features of the Ag NP plasmonic coupling, which are found to be rather different in the NC films with x <10 and x >15. We found that increase of x in the range of 0< x < 10 results in strong enhancement of the electric dipole plasmon mode, whereas optical spectra of the NC films with x > 15 demonstrate pronounced efficiency of tunnelling charge transfer plasmons. Careful analysis of the detected excitations revealed evident conformity in the x -induced alterations of the plasmonic and excitonic modes as hallmarks of plasmon–exciton interactions. The detected plasmonic effects demonstrate great potential of this metal-organic system in molecular sensing, photocatalysis and optoelectronics. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with a detailed study of changes that lithium tantalate (LT) and lithium niobate (LN) single crystals undergo during the annealed proton exchange (APE) process of optical waveguides’ formation. It is a well-known fact that several cases of anomalous behaviour are connected to the APE:LT samples, bringing thus an obstruction for the practical utilization of the APE:LT waveguides. As the LT crystal possesses even better optical properties than the LN crystal (e.g., it is less susceptible to optical damage), it is desirable to provide research focused on its behaviour during the APE process in order to acquire a control over the fabrication of the APE:LT devices. Neutron depth profiling (NDP), elastic recoil detection analysis (ERDA) and heavy ion ERDA (HI-ERDA) were performed to study changes in the surface of the LT and LN Z-cut wafers caused by the APE treatment and to determine the concentration depth profiles of the exchanged ions (lithium and hydrogen). Information on modifications of the crystals during the APE was obtained using X-ray diffraction (XRD) analysis. Optical/waveguiding properties of the samples were obtained by means of the standard mode spectroscopy at 633nm. The experiments proved that the LT is significantly less affected by the APE process compared to the LN and that most characteristics of the APE:LT layers can be easily restored towards that of the virgin crystal by the annealing process. [Copyright &y& Elsevier]

Abstract: Here we present a new method of fabrication of erbium containing thin optical layers that could be interesting for photonics active structures. These layers were fabricated by a purely thermal ion-exchange process at temperatures above the transformation point of the used glasses to minimise internal strain that arose in the layers during the fabrication process. In order to accelerate migration of rather immobile Er3+ ions, we used substrates with a high content of easily exchangeable Li+ ions. The substrates were prepared either as specially designed Li-glasses or glasses with intentionally created Li-containing surface layers. A number of nuclear analytical methods (i.e., Rutherford backscattering spectroscopy—RBS, and neutron depth profiling—NDP), as well as scanning electron microscopy (SEM-EDAX) were used to confirm presence of erbium in the glass surface and to determine the chemical composition of the fabricated layers. Photoluminescence spectra of the fabricated samples were measured to examine desired emission at the wavelength of 1.5μm. [Copyright &y& Elsevier]

The energy density of lithium-metal batteries (LMBs) relies substantially on the thickness of the lithium-metal anode. However, a bare, thin lithium foil electrode is vulnerable to fragmentation due to the inhomogeneity of the lithium stripping/plating process, disrupting the electron conduction pathway along the electrode. Accordingly, the current collector is an integral part to prevent the resulting loss of electronic conductivity. However, the common use of a heavy and lithiophobic Cu current collector results in a great anode mass increase and unsatisfactory lithium plating behavior, limiting both the achievable specific energy and the cycle life of LMBs. Herein, a metal-free polymer-based current collector is reported that allows for a substantial mass reduction, while simultaneously extending the cycle life of the lithium-metal anode. The specific mass of the ultra-light, 10 µm thick polymer-based current collector is only 1.03 mg cm -2 , which is ≈11% of a 10 µm thick copper foil (8.96 mg cm -2 ). As a result, LMB cells employing this novel current collector provide a specific energy of 448 Wh kg -1 , which is almost 18% higher than that of LMBs using the copper current collector (378 Wh kg -1 ), and a greatly enhanced cycle life owing to a more homogeneous lithium deposition., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Driving by interplay between plasmonic and magnetic effects in organic composite semiconductors is a challenging task with a huge potential for practical applications. Here, we present evidence of a quantum plasmon excited in the self-assembled Co x C 60 nanocomposite films with x > 15 (interval of the Co cluster coalescence) and analyse it using the optical absorption (OA) spectra. In the case of Co x C 60 film with x = 16 (LF sample), the quantum plasmon generated by the Co/CoO clusters is found as the 1.5 eV-centred OA peak. This finding is supported by the establishment of four specific C 60 -related OA lines detected at the photon energies E p  > 2.5 eV. Increase of the Co content up to x = 29 (HF sample) leads to pronounced enhancement of OA intensity in the energy range of E p  > 2.5 eV and to plasmonic peak downshift of 0.2 eV with respect to the peak position in the LF spectrum. Four pairs of the OA peaks evaluated in the HF spectrum at E p  > 2.5 eV reflect splitting of the C 60 -related lines, suggesting great change in the microscopic conditions with increasing x. Analysis of the film nanostructure and the plasmon-induced conditions allows us to propose a Rashba-like spin splitting effect that suggests valuable sources for spin polarization.