Changes in Optical Properties of Ce: YAG Crystals under Annealing and Irradiation Processing

Abstract

Changes of optical properties of cerium doped YAG single crystals (0.05, 0.1, 0.2 at. % Ce, and 0.2 at. % Ce "+" 0.1at. % Mg) after thermal annealing at 1400 o C in air or 1200 o C in N 2 +H 2 mixture and subsequent γ or proton irradiation were investigated. For initial Ce 3+ contents <0.05 at. % an increase and for Ce 3+ contents >0,05 at. % a decrease of the final Ce 3+ concentration was observed. Appropriate changes in luminescence of Ce: YAG crystals were observed as a consequence of dopant concentration changes. They were small after γ-irradiation of Ce: YAG crystals with Ce 3+ content >0,05at.% and reached about 100% after γ-irradiation of crystals with Ce 3+ content <0.05 at. %.

Synthesis of YAG:Ce phosphor via different aluminum sources and precipitation processes

“…Yttrium aluminum garnet (Y 3 Al 5 O 12 , YAG) has many applications due to the optical properties and pyroceram structure [1][2][3][4]. Moreover most of the material for applications was doped with a small amount of impurity ions such as Eu, Cr, Tb, Ce to be substituted into the dodecahedral site of the YAG lattices to have different kinds of luminescent properties [5][6][7][8].…”

Synthesis and characterization of YAG:Ce phosphors for white LEDs

“…: first air and then re− ducing atmosphere). Different atmosphere can be used in order to change the defect structure of these crystals, to facilitate the transition from Ce 4+ to Ce 3+ [21,24,26,30,33]. The thermal treatment can be done at atmospheric pressure or under different values of pressure (i.e., 10 -3 Pa, vacuum condition).…”

Synthesis and evolution of crystalline garnet phases in Y3Sc5–xGaxO12

“…When doped with a transition metal or lanthanide ions, YAG represents an important solid-state laser material widely used in luminescence systems, window materials for a variety of lamps and for fibre-optic telecommunication systems [1][2][3][4][5][6]. Aluminates with other crystal structures are also promising materials for optical applications [7][8][9][10][11].…”