Bi³⁺-Sensitized La₂Zr₂O₇:Er³⁺ Transparent Ceramics with Efficient Up/Down-Conversion Luminescence Properties for Photonic Applications

Abstract

Optical gain materials are of great importance for photonic applications, particularly in the realization of high-performance lasers and amplifiers. Unfortunately, the relatively poor thermodynamic stability greatly restricts their applications in harsh environments. Here, promising gain materials with harsh-environment endurance, transparent La2Zr2O7:Er3+,Bi3+ (LZO:Er,Bi) ceramics, were fabricated successfully. The LZO:1% Er,2% Bi ceramics exhibit the highest in-line transmittance of 64.8% at 1300 nm. Enhanced photoluminescence from Er3+-doped LZO sensitized with Bi3+ has been observed. We systematically study the sensitization mechanism of Bi–Er coupling from both up- and down-conversion. The former originates from the energy back-transfer and the modification of the symmetry of the crystal field in the lattice, where the modification of the crystal field is dominant during an up-conversion sensitized process. The latter is attributed to the efficient energy transfer (ET) from Bi3+ to Er3+. The calculated ET efficiency ηET is about 72%. The most probable ET mechanism from Bi3+ to Er3+ in LZO ceramics is the dipole–dipole interaction. The LZO:Er,Bi transparent ceramics with excellent thermal stability, effective luminescence, and a long metastable-level lifetime can be potential candidates as optical gain materials for photonic applications in severe environments.

Multiwavelength Responsive Luminescence for Temperature Sensing and Visualized Information Encoding/Decoding Based on Er3+/Tb3+-Doped Ba2Ga2GeO7 Phosphors

“…A green band composed of two emission peaks located at 525 and 548 nm can be observed in the corresponding UC spectra, which are assigned to Er 3+ 4f → 4f electronic transitions: 2 H 11/2 , 4 S 3/2 → 4 I 15/2. , The optimum concentration of doping ions is determined to be 8%, which is similar to the luminescence behavior excited by 382 nm. Figure d shows the UC emission spectra excited by a 980 nm laser, and the green emission bands located at ∼525 and ∼548 nm can be attributed to 2 H 11/2 , 4 S 3/2 → 4 I 15/2 , while the red emission peaks at 650, 656, 667, 671, and 677 nm are due to the transitions from several sublevels of Stark splitting of 4 F 9/2 to the 4 I 15/2 level under the crystal field, − and the optimal doping concentration of Er 3+ in terms of UC emission is 10%.…”

“…As shown in Figure a, the PLE spectrum monitored at 548 nm exhibits a sharp peak centered at 382 nm, which can be ascribed to the Er 3+ characteristic absorption ( 4 I 15/2 → 4 G 11/2 ) . Under 382 nm irradiation, the PL spectrum is composed of two green emission peaks centered at 525 and 548 nm assigned to the intrinsic Er 3+ : 2 H 11/2 , 4 S 3/2 → 4 I 15/2 electron transitions, respectively Figure b displays the luminescence behavior of BGGO: x Er 3+ ( x = 2%–10%) upon irradiation of 382 nm.…”

Silicate Phosphors BaGa2Si2O8:Ln3+ (Er3+, Ho3+, Yb3+) Equipped with Intrinsic Optical Bistability toward Photonic Barcodes

“…In Figure 2d, the optimum doping content of Er 3+ ions for down-conversion luminescence was 0.03 upon 980 nm excitation, which was consistent with UC emission. The infrared emission centered at 1535 nm was attributed to the transition of Er 3+ : 4 I 13/2 → 4 I 15/2 , 33 and its decline was derived from concentration quenching. The infrared luminescence of Ho 3+ is displayed in Figure 2e, and the band centered at 1205 nm originated from the electronic transition of Ho 3+ : 5 I 6 → 5 I 8.…”

Dy3+‐doped Y2Zr2O7 highly transparent ceramics for ultraviolet excitable warm white light‐emitting applications

“…Usually, the luminescence properties of doped active ions are closely related to the corresponding host material. Among the various ceramic materials, lanthanide zirconate (Ln 2 Zr 2 O 7 ) transparent ceramics have increasingly attracted attention due to their large unit cell, high solubility range, high tolerance to defects, and homogeneous and higher refractivity 17–19 . In particular, the representative Y 2 Zr 2 O 7 (YZO) ceramics with a relatively lower phonon energy of about 700 cm −1 , which is lower than that of the state‐of‐the‐art YAG transparent matrix (850 cm −1 ), could lead to a high photoluminescence efficiency, making them are exciting potential for photonic applications such as scintillators and optical gain materials 20,21 .…”

“…Among the various ceramic materials, lanthanide zirconate (Ln 2 Zr 2 O 7 ) transparent ceramics have increasingly attracted attention due to their large unit cell, high solubility range, high tolerance to defects, and homogeneous and higher refractivity. [17][18][19] In particular, the representative Y 2 Zr 2 O 7 (YZO) ceramics with a relatively lower phonon energy of about 700 cm −1 , which is lower than that of the state-of-the-art YAG transparent matrix (850 cm −1 ), could lead to a high photoluminescence efficiency, making them are exciting potential for photonic applications such as scintillators and optical gain materials. 20,21 Although some original works about lanthanide-doped YZO transparent ceramics have been reported and demonstrated their lightemitting applications, [21][22][23][24][25] there is no warm white emitting converter excited by a UV light device in YZO host have been reported so far.…”