title: High pressure and time-resolved luminescence spectra of Ca3Y2(SiO4)3 doped with Eu2+ and Eu3+.
abstract: Tricalcium diyttrium trisilicon oxide, Ca(3)Y(2)(SiO(4))(3) doped with Eu(2+) and Eu(3+) belongs to a very limited number of hosts able to accommodate both Eu(3+) and Eu(2+) ions, which might make it useful for white light emitting diodes (WLEDs) based on UV chip technology. In this contribution we present a detailed study of photoluminescence kinetics and high pressure spectroscopy of Eu(3+) and Eu(2+) doped Ca(3)Y(2)(SiO(4))(3). At ambient pressure and room temperature, under excitation with near-UV radiation, a broad emission band from 400 to 550 nm due to the 4f(6)5d(1)→4f(7)((8)S(7/2)) transition in Eu(2+) was observed, as well as several emission peaks in the region between 550 and 710 nm, ascribed to the (5)D(0)→ (7)F(J) (J = 0-4) transitions in Eu(3+). The bluish green luminescence related to Eu(2+) in the Ca(3)Y(2)(SiO(4))(3) exhibits a small red pressure-induced shift reaching -5.2 cm(-1)/kbar. The red shifts of the luminescence lines related to Eu(3+) ion emission vary from 0.15 to -0.54 cm(-1)/kbar. Time-resolved photoluminescence was measured at different temperatures and pressures. Luminescence decay traces were studied for the bluish green emission band of Eu(2+) and for the red emission peak due to the (5)D(0) →  (7)F(2) transition of Eu(3+). Decay times slightly decreased with increasing pressure.
authors.affiliation: Institute of Experimental Physics, University of Gdansk, Poland. fizab@ug.edu.pl
authors.forename: A
authors.initials: A
authors.lastname: Baran
authors.forename: S
authors.initials: S
authors.lastname: Mahlik
authors.forename: M
authors.initials: M
authors.lastname: Grinberg
authors.forename: E
authors.initials: E
authors.lastname: Zych
mesh_terms: D002118:Calcium / Q000737:chemistry*; D005063:Europium / Q000737:chemistry*; D008029:Lighting / Q000379:methods*; D008163:Luminescent Measurements / Q000379:methods*; D008422:Materials Testing; D011312:Pressure; D013431:Sulfates / Q000737:chemistry; D015019:Yttrium / Q000737:chemistry*
chemical_list: D013431:Sulfates; D005063:Europium; D015019:Yttrium; D002118:Calcium