Yekaterinburg, Russia
Yekaterinburg, Russia

Time filter

Source Type

Osipov V.V.,Institute of Electrophysics UrB RAS | Ishchenko A.V.,Ural Federal University | Shitov V.A.,Institute of Electrophysics UrB RAS | Maksimov R.N.,Institute of Electrophysics UrB RAS | And 8 more authors.
Optical Materials | Year: 2016

Highly transparent YAG:Ce ceramics (transmission of 72-82% for 2-mm-thick samples in 550-900 nm wavelength range) were fabricated by solid-state reactive sintering using a mixture of Ce2xY2-2xO3 (x = 0.001, 0.01, 0.03, and 0.05) and Al2O3 nanopowders synthesized by laser ablation with an additional round of pre-calcining before compaction. The synthesized YAG:Ce ceramic materials showed intense luminescence with a maximum at 525-545 nm. The measured absolute light yields of the synthesized YAG:Ce ceramics were 18-21 photon/MeV for 1-5 at.% Ce and 5 photon/MeV for 0.1 at.% Ce. The energy resolutions of the fabricated thin ceramic samples (2 mm) under 662 keV gamma ray were measured to be 10-15%. The decay curves of scintillations consisted of two components with the decay times depending on the Ce3+ concentration. The sample doped with 5 at.% of Ce exhibited the main fast component with 26 ns decay time. The measured data was compared to that of YAG:Ce and well-known CsI:Tl single crystal scintillators. The influence of dopant concentration on the optical, luminescence and scintillation properties was discussed. © 2016 Elsevier B.V.

Osipov V.V.,Institute of Electrophysics UrB RAS | Shitov V.A.,Institute of Electrophysics UrB RAS | Solomonov V.I.,Institute of Electrophysics UrB RAS | Solomonov V.I.,Ural Federal University | And 3 more authors.
Ceramics International | Year: 2015

This work reports the fabrication of composite transparent ceramics consisting of a Nd:YAG central part and a Cr4+:YAG edge cladding. The central part of ceramics was shaped into 14mm-diameter disk or 11mm-side square and an outer diameter of the edge cladding was 18mm or 23mm, respectively. The central part of ceramics exhibited an optical transmittance of ~84% at the wavelength of 1.06μm. The concentration of Cr4+ in Cr4+:YAG ceramics with three different compositions was evaluated using measured transmission spectra and reported absorption cross sections. Taking into account the infeasibility condition for self-excitation, the optimal composition of edge cladding was estimated to be 2.5at% Cr, 0.25at% Ca:YAG. © 2015 Elsevier Ltd and Techna Group S.r.l.

Maksimov R.N.,Ural Federal University | Esposito L.,CNR Institute of Science and Technology for Ceramics | Hostasa J.,CNR Institute of Science and Technology for Ceramics | Shitov V.A.,Institute of Electrophysics UrB RAS | Belov P.A.,Ural Federal University
Materials Letters | Year: 2016

In this work we report on the effects induced by calcining monoclinic ytterbium-doped lutetium oxide (Yb: Lu2O3) nanoparticles on their phase transformation and densification behavior. Morphology and phase evolution of powder synthesized by laser ablation were studied by scanning electron microscopy and high temperature X-ray diffraction, respectively. The powder consisted of soft agglomerates comprising 15–25 nm spherical particles with monoclinic crystal structure. The beginning of phase transformation depends on the particle packing density, resulting in the temperatures of 700 °C and 1000 °C for loose and pressed powder, respectively. Transformation-assisted vacuum sintering of as-synthesized powder at 1780 °C for 20 h resulted in a core-shell and porous microstructure of Yb: Lu2O3 ceramic due to significant density decrease and obstructed densification during phase conversion. On the other hand, transparent Yb: Lu2O3 ceramic exhibiting an optical transmittance of 76.6% at the wavelength of 1080 nm was obtained using additional calcining of powder. © 2016 Elsevier B.V.

Loading Institute of Electrophysics UrB RAS collaborators
Loading Institute of Electrophysics UrB RAS collaborators