Luminescence of YAG:Tm, Tb

Abstract

Two rare earth cations, thulium (Tm) and terbium (Tb) have been incorporated into a yttrium aluminum garnet (YAG) host material to obtain a blue phosphor. Thulium concentrations of up to 5% yield a saturated dark blue phosphor which exhibits a low efficiency. The highest efficiency for YAG:Tm occurs at a Tm concentration of 2%. A 0.5% concentration of terbium yields an unsaturated blue phosphor with an efficiency of approximately a factor of 15 times greater than that of Tm. The cathodoluminescence spectrum of YAG:Tm, Tb depicts features identifiable with YAG:Tb even at low Tb concentrations (0.5%). The light emitted by a Tb, Tm coactivated phosphor exhibits a clear shift toward the green region of the spectrum. There appears to be a resonant energy transfer from the 1D2 Tm3+ state to the 5D4 Tb3+ state. In the case of small concentrations of Tb in YAG, thulium behaves as a sensitizer for Tb cathodoluminescence.

Synthesis of polycrystalline yttrium iron garnet and yttrium aluminium garnet from organic precursors

“…Yttrium iron garnet (YIG) is a ferrimagnetic material which is used as a filter in microwave circuitry and also as an electronic resonator [1]. Yttrium aluminium garnet (YAG) is a hard material which can be used as a refractory coating for electronic devices and as the host for a series of robust rare-earth-doped phosphors [2]. These two mixed metal oxide phases, which have a body centred cubic crystal structure, belong to the garnet series of ceramic compounds which have the same crystal structure as the mineral grossalurite, Ca3A1 z [SiOr 3.…”

Sol–gel synthesis and photoluminescence of K2NiF4-type structure phosphors CaxSr1−xGdyY1−yAlO4:zEu3+ with hybrid precursors

“…3. We take representative excitation spectrum of CaGdAlO 4 As it shown in Fig. 4, the emission spectra of CaGdAlO 4 :zEu 3+ (z = 0.01, 0.02, 0.03, 0.05, 0.07 mmol) verifies the fact that the luminescence properties of Eu 3+ depend strongly on their doping concentration in the host lattices.…”

“…Their original particular interest were inorganic luminescent materials, practical applications in almost and device involving the artificial production of light. Cathode ray tubes lamps, X-ray detectors field emission display (FED) and plasma displays (PDP) are well known examples [3][4][5][6] and all these industrial appliances have increased the demand for these materials with increasingly better characteristics in term of stability, brightness and industrial processing ability [7,8]. To acquire more efficient luminescent materials, great efforts have been devoted to the rare-earth activated phosphors because of their good luminescent characteristics, stability in high vacuum, and absence of corrosive gas emission under electron bombardment compared with currently used sulfide-based * Corresponding author.…”

Sensitivity of a temperature sensor, employing ratio of fluorescence power in a band

“…Rare-earth doped materials have been used extensively as temperature sensors [1][2][3][4][5], because their emission is temperature dependent. Homogeneous broadening of the line widths is observed due to the changing population of the energy levels with temperature.…”