Browsing by Author "Untila, D."

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    Luminescence of β-Ga2O3 Nanoforms Obtained by Oxidation of GaSe Doped with Eu [Articol]
    (Springer, Cham, 2020) Sprincean, Veaceslav; Untila, D.; Chirița, Arcadii; Evtodiev, I.; Caraman, I.
    The GaSe single crystals were doped with Eu in the process of their synthesis and growth. The oxide of β-Ga2O3 doped with Eu in the form of massive nanowires was obtained by thermal treatment (TT) in the atmosphere of GaSe single crystals doped with 1.0 and 3.0 at.% of Eu. The crystalline structure, surface morphology and photoluminescence spectra of GaSe:Eu and β-Ga2O3:Eu single crystals were studied. The Photoluminescence (FL) spectrum of GaSe doped with 1.0 at.% of Eu at room temperature is formed as a result of transitions of 5D0 →7F1 to Eu3+ ion and as a result of radiation annihilation of n = 1 excitons in GaSe. The FL spectra of Ga2O3:Eu was interpreted on the basis of the energy level diagram of electrons in Eu3+ ion.
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    Preparation and optical properties of lamellar GaSe -ZnSe nanocomposites [Articol]
    (2015) Caraman, M.; Untila, D.; Canțer, V.; Evtodiev, Igor; Caraman, Iu.; Susu, O.; Leontie, L.
    ZnSe-GaSe nanocomposite plates photoluminescent in a photon energy range of 1.80−2.64 eV were obtained via exposing GaSe single-crystal plates to a Zn-vapor heat treatment at temperatures of 673−873 K. The photoluminescence spectrum is dominated bythe self-activated emission band of ZnSe witha maximum at 2.04 eV. The average size of the ZnSe crystallites is ~45 nm. The absorption spectrum of the composite consists of two regions characteristic of direct optical transitions in GaSe crystals with a band gap of 1.99 eV and ZnSe crystallites with aband gap of 2.56 eV at room temperature.