Optimizing Broadband Near-Infrared Emission in Bi/Sn-Doped Aluminosilicate Glass by Modulating Glass Composition

The Bi/Sn-doped aluminosilicate glass samples were prepared using a melting–quenching method and their near-infrared (NIR) emission properties were studied. An ultra-broadband NIR emission ranging from 950 nm to 1600 nm was observed in all samples under 480 nm excitation, which covered the whole fiber low-loss window. The NIR emission spectrum showed that the maximum emission peak was about 1206 nm and the full width at half maximum (FWHM) was about 220 nm. Furthermore, the NIR emission intensity strongly depends on the composition of the glass, which can be optimized by modulating the glass composition. The Bi0 and Bi+ ions were the NIR luminescence source of the glass samples in this paper. The Bi/Sn-doped aluminosilicate glass has the potential to become a new type of core fiber material and to be applied to optical fiber amplifiers (OFAs), based on its excellent performance in ultra-broadband NIR emission

Preparation and characterization of quarter-wave plate at 12.4 μm based on CdSe single crystal

CdSe single crystal with good optic properties is great candidates for optical devices. In this paper, CdSe single crystal was grown by the modified vertical unseeded vapor sublimation method with the diameter of 36 mm and the length of 40 mm. The quarter wave plates of CdSe single crystal with size of 20 mm × 20 mm × 3 mm was cut along the (001) orientation. The transmittance of the CdSe wave plate was about 69% in the range of 8–14 μ m, where the absorption coefficient was about 0.04 cm ^−1 . The phase delay was 90.71176° at 12.4 μ m, which less than 5%. This work disclosures a high-quality and large size wave plate of CdSe single crystal, such wave plate has wide application prospects in mid-infrared

Aggregation of ODC(I) and POL Defects in Bismuth Doped Silica Fiber

First-principles calculations were used to simulate the aggregation of the peroxy chain defect POL and the oxygen vacancy defect ODC(I). Defect aggregation’s electronic structure and optical properties were investigated. The two defects were most likely to accumulate on a 6-membered ring in ortho-position. When the two defects are aggregated, it is discovered that 0.75 ev absorption peaks appear in the near-infrared band, which may be brought on by the addition of oxygen vacancy defect ODC(I). We can draw the conclusion that the absorption peak of the aggregation defect of ODC(I) defect and POL is more prominent in the near infrared region and visible light area than ODC(I) defect and POL defect