TITLE:
Photoluminescence Compounds ZnGa2Se4 and ZnGa2Se4: Eu2+
AUTHORS:
Oktay Tagiyev, Saida Asadullayeva, Gurban Eyyubov, Ulvi Kasumov, Kenan Tagiyev
KEYWORDS:
Ternary Chalcopyrite; Photoluminescence; Rare-Earth Elements
JOURNAL NAME:
Journal of Modern Physics,
Vol.3 No.8,
August
15,
2012
ABSTRACT: Photoluminescence (PL) spectra measurements have been carried out in the ternary chalcopyrite semiconductor compounds ZnGa2Se42Se4: Eu2+ using single-wavelength excitation of a Hg lamp with λ = 365 and 375 nm. Measurements were performed at the temperature range of (120 ~ 220 K) and (110 ~ 230 K) for ZnGa2Se4 and ZnGa2Se4:Eu2+, respectively. No PL was observed for both crystals at the temperatures higher than 220 K (ZnGa2Se4) and 230 K (ZnGa2Se4:Eu2+). At temperatures lower than ~220 K and ~230 K one and three lines were observed for ZnGa2Se4 and ZnGa2Se4: Eu at 591 nm and 566, 591, 646 nm, respectively. 566 nm line was assigned as due of the 4f65d→ 4f7 (8S7/2) transition of Eu2+ ions, whereas the rest two lines were attributed to the donor-acceptor recombination pairs. Probability of non-radiation transfers (A = 108 ~109 s-1), energy of optical phonons (hω= 25 ~ 30 meV), Huan Rice parameter (S = 8 ~ 10), energy of thermal quenching (△E = 0.02 ~ 0.06 eV) were determined from the tem-perature dependences of the full width at half maximum (FWHM = Г(T)).