Cietvielu fizikas institūts / Institute of Solid State Physics: Recent submissions
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Multisite formation in gadolinium doped SrF2 nanoparticles
(Elsevier B.V., 2018)Gadolinium doped SrF2 nanoparticles have been synthesized by the precipitation method and characterized by site-selective optical spectroscopy and electron paramagnetic resonance (EPR) spectroscopy methods at cryogenic ... -
Chapter 8: EPR in glass ceramics
(Elsevier B.V., 2019)The development of novel materials requires a profound understanding of the relationship between a material's performance and its structural properties. Electron paramagnetic resonance (EPR) is a well-established technique ... -
Cubic and rhombohedral Ba4Lu3F17:Er3+ in transparent glass ceramics: Crystallization and upconversion luminescence
(Elsevier B.V., 2018)Novel Er3+ doped glass ceramics containing Ba4Lu3F17 nanocrystals were successfully prepared by heat treatment of melt-quenched glasses. Highly efficient upconversion luminescence was detected under near-infrared excitation ... -
Crystalline phase detection in glass ceramics by EPR spectroscopy
(AIP Publishing, 2018)The advances of EPR spectroscopy for the detection of activators as well as determining their local structure in the crystalline phase of glass ceramics is considered. The feasibility of d-element (Mn2+, Cu2+) and f-element ... -
Electron paramagnetic resonance and photoluminescence investigation of europium local structure in oxyfluoride glass ceramics containing SrF2 nanocrystals
(Elsevier B.V., 2017)Different compositions of europium doped aluminosilicate oxyfluoride glass ceramics prepared in air atmosphere have been studied by electron paramagnetic resonance (EPR) and optical spectroscopy methods. X-ray diffraction ... -
EPR characterization of erbium in glasses and glass ceramics
(AIP Publishing, 2020)Electron paramagnetic resonance (EPR) is a well-established spectroscopic technique for electronic structure characterization of rare-earth ion impurities in crystalline and amorphous hosts. EPR spectra of erbium-doped ... -
Upconversion luminescence in transparent oxyfluoride glass ceramics containing hexagonal NaErF4
(Elsevier B.V., 2019)Transparent oxyfluoride glass ceramics containing hexagonal NaErF4 nanocrystals were synthesized by a heat treatment of a precursor glass obtained by the melt quenching technique. Combined X-ray diffraction (XRD) and ... -
Upconversion luminescence of Er3 +/Yb3 + and their role in the stabilization of cubic NaLaF4 nanocrystals in transparent oxyfluoride glass ceramics
(Elsevier B.V., 2018)Novel Er3 + and Yb3 + doped transparent oxyfluoride glass ceramics containing NaLaF4 nanocrystals were prepared from oxyfluoride glasses with general composition of Na2O-NaF-LaF3-Al2O3-SiO2. The crystallization processes, ... -
Ordering of fluorite-type phases in erbium-doped oxyfluoride glass ceramics
(Elsevier B.V., 2018)In this study, novel transparent Er3+ doped glass ceramics were prepared from melt-quenched oxyfluoride glasses with general composition of Na2O-NaF-BaF2-YbF3-Al2O3-SiO2. The crystallization of fluorite (BaF2, BaF2-YbF3, ... -
Phase transitions and upconversion luminescence in oxyfluoride glass ceramics containing Ba4Gd3F17 nanocrystals
(Elsevier B.V., 2017)Novel transparent Er3+ doped oxyfluoride glass-ceramics containing Ba4Gd3F17 nanocrystals were prepared by melt quenching followed by heat treatment of as-prepared glasses. The phase composition and microstructure were ... -
Upconversion luminescence of a transparent glass ceramics with hexagonal Na(Gd,Lu)F4 nanocrystals
(Elsevier B.V., 2017)Novel Er3+ doped transparent glass ceramics containing hexagonal Na(Gd,Lu)F4 nanocrystals were prepared from oxyfluoride glasses. The distribution of rare earth ions in the crystalline and glassy phase has been analyzed ... -
Thin film organic thermoelectric generator based on tetrathiotetracene
(Wiley-VCH Verlag, 2017)Thin films of p- and n- type organic semiconductors for thermo-electrical (TE) applications are produced by doping of tetrathiotetracene (TTT). To obtain p-type material TTT is doped with iodine during vacuum deposition ... -
Thickness-dependent properties of ultrathin bismuth and antimony chalcogenide films formed by physical vapor deposition and their application in thermoelectric generators
(Elsevier B.V., 2021)In this work, a simple cost-effective physical vapor deposition method for obtaining high-quality Bi2Se3 and Sb2Te3 ultrathin films with thicknesses down to 5 nm on mica, fused quartz, and monolayer graphene substrates is ... -
Study of the thermochromic phase transition in CuMo1−xWxO4 solid solutions at the W L3-edge by resonant X-ray emission spectroscopy
(Elsevier Ltd., 2021)Polycrystalline CuMo1−xWxO4 solid solutions were studied by resonant X-ray emission spectroscopy (RXES) at the W L3-edge to follow a variation of the tungsten local atomic and electronic structures across thermochromic ... -
Simulation of Young's moduli for hexagonal ZnO [0 0 0 1]-oriented nanowires: first principles and molecular mechanical calculations
(IOP Publishing, 2017)Morphologically reproducible wurtzite-structured zinc oxide nanowires (ZnO NWs) can be synthesized by different methods. Since ZnO NWs have been found to possess piezoelectricity, a comprehensive study of their mechanical ... -
Orientation of the electric field gradient and ellipticity of the magnetic cycloid in multiferroic BiFeO3
(Taylor and Francis Ltd., 2017)The paper deals with the hyperfine interactions observed on the 57Fe nucleus in multiferroic BiFeO3 by means of the 14.41-keV resonant transition in 57Fe and for transmission geometry applied to the random powder sample. ... -
Multimode time-dependent gyrotron equations for different time scales
(American Institute of Physics Inc., 2017)Development of gyrotrons requires careful understanding of different regimes of gyrotron oscillations. For a long time, the gyrotron theory was developed assuming that the transit time of electrons through the interaction ... -
Anisotropic photoluminescence of nonpolar ZnO epilayers and ZnO/Zn1 −xMgxO multiple quantum wells grown on LiGaO2 substrate
(OSA - The Optical Society, 2020)The temperature-dependent polarized photoluminescence spectra of nonpolar ZnO samples were investigated by 263 nm laser. The degree of polarization (DOP) of m-plane quantum wells changes from 76% at 10 K to 40% at 300 K, ... -
Structural, magnetic, dielectric and mechanical properties of (Ba,Sr) MnO3 ceramics
(Elsevier Ltd, 2017)Ceramic samples, produced by conventional sintering method in ambient air, 6H-SrMnO3 (6H-SMO), 15R-BaMnO3 (15R-BMO), 4H-Ba0.5Sr0.5MnO3 (4H-BSMO) were studied. In the XRD measurements for SMO the new anomalies of the lattice ... -
All-organic electro-optic waveguide modulator comprising SU-8 and nonlinear optical polymer
(OSA - The Optical Society, 2017)In this paper we describe the principles of operation as well as the fabrication and testing steps of an all-organic waveguide modulator. The modulator comprises an SU-8 core and an electro-optic host-guest polymer cladding. ...