Redox equilibrium and NIR luminescence of Bi2O3-containing glasses

Linear and nonlinear optical properties of glasses doped with Bi nanoparticles

“…No absorption band was observed in the 300-2500 nm region of the as made glass. While two surface plasmon resonance (SPR) peaks at 460, and 506 nm were observed in the glass sample after heat treatment at 460°C [24,25]. The intensity of SPR peaks increases as the treat temperature increases from 460°C to 500°C which can be ascribed to the increases of particle size [14,15,18].…”

“…It was found that the coloration of Bi-containing borate glasses are strongly affected by melting temperature [24,25]. The color becomes deeper and deeper with increases of temperature and finally metallic Bi colloids precipitated.…”

“…Recently, researchers have expressed their extensive interest in the bismuth oxide glasses due to their excellent optical properties such as high refractive index, broad band near infrared (NIR) luminescence [22,23], etc. It is well known that bismuth oxide glasses are often obtained in dark-brown or black color, which depends on glass composition and melting conditions [24,25]. This indicates that bismuth is very sensitive to preparation conditions and readily reduced to metallic Bi.…”

Bismuth-doped optical fibers: a challenging active medium for near-IR lasers and optical amplifiers

“…Excessive reduction results in the formation of Bi clusters and colloids, and optical losses increase. 8,13 At present, there are several hypotheses concerning the origin of near-IR emission from Bi-doped glass: Bi 1 , Bi clusters, BiO, Bi 2 2 /Bi 2 , Bi 2 2 /Bi 2 22 , point defects, Bi 0 and others have been examined, but none has been directly confirmed to be the defining factor. These hypotheses have been analyzed in detail in Ref.…”

Surface-luminescence from thermally reduced bismuth-doped sodium aluminosilicate glasses

“…Several different approaches have been attempted to obtain and optimize NIR luminescence from bismuth-doped glasses by manipulating the oxidation state of bismuth. These approaches include controlling the optical basicity of the glass [19][20][21], controlling the melting atmosphere and temperature [22,23], adding oxidation [24] or reduction agents [23] to the batch, tempering the glass [23], crystallizing the glass [25], and irradiating the glass with femtosecond lasers, γ-rays, or high-energy electron rays [26][27][28]. Based on these previous efforts it can be stated that the occurrence of NIR-active Bi species is highly sensitive to numerous parameters [29] and that its optimization requires delicate tuning of all parameters which affect the oxidation state of bismuth [23].…”