Cyan-white-red luminescence from europium doped Al2O3-La2O3-SiO2 glasses

Aluminum-lanthanum-silicate glasses with different Eu doping concentration have been synthesized by conventional melt-quenching method at 1680 degrees C in reductive atmosphere. Under 395nm excitation, samples with low Eu doping concentration show mainly the cyan broad emission at 460nm due to 4f(6)5d(1)-4f(7) transition of Eu2+; and the samples with higher Eu doping concentration show mainly some narrow emissions with maximum at 616nm due to D-5(0)-F-7(J) (J=0, 1, 2, 3, 4) transitions of Eu3+. Cyan-white-red tunable luminescence under 395nm excitation has been obtained by changing the Eu doping concentration. (C) 2008 Optical Society of America.