Multicenters in Ce3+ visible emission of YAG ceramics

Spectral, energy resolution properties and green-yellow LEDs applications of transparent Ce3+:Lu3Al5O12 ceramics

“…According to the Gaussian curve fitting, it can be seen that the emission curve was well fitted by a septuplet Gaussian function (shown in red dash line), indicating that the photoluminescence spectra were composed of seven broad bands centered at about 516, 524, 535, 549, 568, 594 and 637 nm, respectively, as shown in color dash lines. These emission bands were ascribed to the electron transitions from the lowest crystal-field-split level of the 5d 1 ( 2 D) excited state to the Stark levels 2 F 5/2 (1-3) and 2 F 7/2 (4-7) [22,23], as shown in Fig. 8(a), where the Ce 3+ has a 4f 1 electronic configuration and its excited configuration is 4f 0 5d 1 state.…”

“…In the case of crystal field splitting, more than two 5d components produced depending on the LuAG host lattice, while the lowest crystal field component was the most important factor because higher energy level states would relax to lower energy states. Meanwhile, due to so called anti-site defects, i.e, ions in the Al positions, at least three types of Ce 3+ emitting centers were formed in the LuAG garnet host [22,23]. As a result, the 4f electron of the 4f 1 configuration forms seven energy levels by crystal field splitting, as shown in Fig.…”

“…We measured the chromaticity parameters, such as CIE color coordinates, color rendering index (CRI), correlated color temperature (CCT), luminous efficacy (LE) and LE of radiation (LER) by using the integrated optical and electrical measuring system for LEDs (Hangzhou Everfine Photo-electricity Information Co. Ltd. China), the forward current of the blue chip was fixed at 50 mA. Scintillation energy resolution were investigated under excitation by 511 keV photons from 22 Na. The X-ray photoelectron spectroscopy (XPS) analyses were performed on a Thermo ESCALAB 250Xi using Al-K␣ radiation.…”

YAG:Ce 3+ piezo‐spectroscopy: A high‐sensitive method used for stress characterization of thermal barrier coating

“…Schematic diagram of the YAG:Ce 3+ luminescence piezo‐spectroscopic principle: (A) Ce 3+ under stress; (B) Ce 3+ energy level transition 28 ; (C) frequency shift of the YAG:Ce 3+ luminescence band under stress…”

Stress- and Temperature-Dependent Wideband Fluorescence of a Phosphor Composite for Sensing Applications

“…The garnet structure possesses several types of positions for the accommodation of dopant ions [31,32]. Dopant pairs/clusters can possibly produce lower energy sites in the Lu 3 Al 5 O 12 matrix and then the emission spectra show a strong red shift [33].…”