Hydroxyl-free quartz glass for low-loss fiber optical waveguides and its comparative radiation-optical properties

Luminescence of localized states in silicon dioxide glass. A short review

“…Some samples were produced without step of washing in oxygen [23]. A high level of oxygen deficiency was provided by reaction of cristobalite with silicon vapor [16,21]. Some aluminium doped samples without alkali ions codoping were studied for comparison [19,20].…”

“…These samples include some made by the KS-4V method described in [21] and some made by SPCVD methods [22]. All samples were pure dry silica (the level of metallic impurities is about 10 − 6 wt.% and content of OH group is about 10 − 7 wt.%, [21]). The method of preparation was based on electrofusion of cristobalitised synthetic silicon dioxide.…”

Luminescence of fluorine-doped and non-doped silica glass excited with an ArF laser

“…The samples were produced as KC-4B (or the same KS-4V) silica, Ref. [9], with the difference that the melting was conducted in a pure SiF 4 atmosphere, which however contained some amount of HF. The detected concentration of OH groups is 7.5 ppm.…”

Sub-band-gap-excited luminescence of localized states in SiO2–Si and SiO2–Al glasses

“…The method of preparation was by electrofusion of cristobalitized synthetic silicon dioxide. The high level of oxygen deficit (about 10 À2 wt%) was achieved by reaction of the cristobalite with silicon vapor [21]. Another sample of silica glass was doped with 0.025 wt% of Al 2 O 3 by adding alumina to synthetic silicon dioxide powder before electrofusion.…”

“…The high purity sample for this investigation was a Type IV silica known as KS-4 V [7,21]. The method of preparation was by electrofusion of cristobalitized synthetic silicon dioxide.…”