Rare-Earth-Doped Low Phonon Energy Halide Crystals for Mid-Infrared Laser Sources

Upconversion Luminescence Properties of Pr3+-Doped BaYF5 Nanoparticles Prepared by Microwave Hydrothermal Method

“…A powerful feature of the rare-earth elements is that their 4f energy levels are almost independent of the host. Since the phonon energy of halidesfluorides (<600 cm –1 ), chlorides (<300 cm –1 ), bromides (<190 cm –1 ), and iodides (<160 cm –1 )is significantly lower compared to oxygen-containing matrices, they are good hosts for highly efficient luminescence due to the low probability of nonradiative phonon-assisted transitions. , Among all halides, fluorides have the highest thermal and chemical stabilities and radiation resistance. All yttrium-based fluorides are of considerable interest for the Y 3+ ion has a similar ionic size and the same charge as the lanthanide ions.…”

Optical properties of Pr3+-, Ce3+-, and Eu3+-doped ternary lead halides

“…Incorporating Pr 3+ in low phonon energy halide hosts allows the possibility to extend emission studies into the mid-infrared (mid-IR) regime. A few studies were reported on the 5 µm laser potentials of 3 H 5 3 H 4 transition from Pr 3+ doped ternary halides such as KPb 2 Cl 5 , KPb 2 Br 5 , Tl 3 PbBr 5 , and CsCdBr 3 [15][16][31][32]. Mid-IR fluorescence properties of Pr 3+ doped low phonon energy crystals and their laser relevant parameters are of considerable interest for laser operations due to broad emissions, reasonably high-emission cross-sections, and long lifetime of several milliseconds (~3-29 ms) [15][16][31][32].…”

“…Binary lead halides (PbCl 2 , PbBr 2 , PbI 2 ) and ternary lead halides (KPb 2 Cl 5 and KPb 2 Br 5 ) are regarded as wide-gap semiconductors with band gap energies ranging from ~2.5 eV to 4.8 eV [28][29][30][31]. They are also considered nonhygroscopic crystals with narrow phonon spectra of 140-203 cm -1 [12][13][14][15].…”

Theoretical and experimental study on the electronic and optical properties of K0.5Rb0.5Pb2Br5: a promising laser host material

“…For the last two decades, rare earth-doped borates and halides have been intensively studied and developed as they possess outstanding properties including good physical and chemical stability, high optical quality, large dimension, and moisture resistance. 5,6 Recently, increasing attention has been paid to the rare-earth doped double halides as they can operate in the mid-IR range. 7 Especially, the active crystal hosts with general formula APb 2 B 5 (A ¼ K, Rb; and B ¼ Cl, Br) are of great interest owing to their low phonon energy of about 140 cm À1 which inhibits the non-radiative transition rate and increases the quantum yield.…”