Optical and spectroscopic study of erbium doped calcium borotellurite glasses

Design Principles for 3d Electron Transfer in a Ga-Based Garnet To Enable High-Performance Reversible Thermochromic Material Color Maps

“…The optical properties of all samples were studied by UV–vis and NIR (200 nm < λ < 1200 nm) diffuse reflectance and absorption spectra, and the spectra (Kubelka–Munk transformed reflectance) are displayed in Figure . The spectra of Er 3 Ga 5 O 12 show a number of absorption bands, which are at 355.6, 362.5, 378.3, 406.2, 441.2, 449.9, 486.7, 525.0, 542.5, 652.6, 787.2, and 962.0 nm, originating from the Er 3+ transitions between the ground state ( 4 I 15/2 ) and excited states ( 4 G 7/2 , 4 G 9/2 , 4 G 11/2 , 2 H 9/2 , 4 F 3/2 , 4 F 5/2 , 4 F 7/2 , 2 H 11/2 , 4 S 3/2 , 4 F 9/2 , 4 I 9/2 , and 4 I 11/2 ). − Compared with other transitions, the 4 I 15/2 → 2 H 11/2 transition has a high intensity, complies with the selection rules |Δ L | ≤ 2, |Δ J | ≤ 2, and Δ S = 0, and is known as a hypersensitive transition. , Figure a shows that the changes in the absorption behavior of Cr 3+ -doped samples are the additions of two wide absorption bands at 441.2 and 612.4 nm, which were related to Cr 3+ d–d transitions, , and the absorption intensity gradually increased with an increase in the Cr 3+ doping amount. − The absorption bands at 441.2 and 612.4 nm correspond to 4 A 2g → 4 T 1g and 4 A 2g → 4 T 2g transitions of Cr 3+ in the octahedral site, respectively. − On the basis of the optical properties, the colors of Cr 3+ -doped samples are attributed to the Cr 3+ d–d transition in purple and orange regions, and the green color gradually became deeper with an increase in the Cr 3+ doping amount, findings in agreement with the absorption band for the d–d transition becoming gradually stronger. Figure b shows the absorption behavior of Mn 3+ -doped samples.…”

Optical, Physical and Structural Properties of Er3+ Doped Low‐Phonon Energy Vitreous Matrix: ZnO‐B2O3‐TeO2

“…This also results in the formation of non‐bridging oxygens (NBOs) . Since NBOs bind an excited electron less tightly than bridging oxygens, the NBOs are more polarizable than bridging oxygens . This leads to decrease in the value of optical band gap.…”

“…B 2 O 3 is added in the present system because of its glass forming ability, good rare earth ion solubility, and hardness . Since, ZnO can occupy both network forming and network modifying positions in borate and tellurite glasses, therefore it can act as a useful modifier that increases the rigidity of the network, glass forming range and stability, lowers the viscosity and improves the transparency to make the glasses less prone to moisture …”

“…Earlier research on fiber lasers and fiber amplifiers was based on silica and fluoride based glasses, however the former suffer from their intrinsic high phonon energy whereas the latter has poor stability and chemical durability. There are many studies on tellurite glasses doped with different rare earths and modifiers however the literature reporting optical, structural and physical studies of Er 3+ doped boro‐tellurite glasses is scarce …”

DC Conductivity of Heavy Metal Oxide (Bi2O3) Boro-Tellurite Glasses: Effect of Eu2O3

“…But tellurite based glasses show good chemical durability, low melting point, better optical properties, and good mechanical strengths. Glass forming ability of TeO2 can be enhanced by adding other glass formers, and among all available glass formers, boron oxide is well suited to TeO2 due to its low melting, high thermal stability, and high glass-forming ability even with regular quenching rates [24][25][26][27][28]. Additionally, TeO2-based glasses [12,13], unlike the transition metal ions (TMI), have been measured to have higher electrical conductivity than silicate, phosphate, and borate samples.…”