Investigation on broadband near-infrared emission in Yb3+/Ho3+ co-doped antimony–silicate glass and optical fiber

In the paper antimony–silicate glass and double-clad optical fiber co-doped with ytterbium and holmium ions were investigated. Absorption spectra in infrared (FT-IR) showed characteristic bands: 445, 605, 1037, 1168 cm−1 coming from the vibration of chemical bonds of SbO3 and SiO4, respectively. The combination of relatively low phonon energy with a capability for greater separation (avoiding clustering) of optically active centers in the fabricated glasses should allow an effective expansion of spontaneous emission band. The highest intensity of emission at the wavelength of λe = 1950 nm resulting from energy transfer between Yb3+ → Ho3+ ions was observed in the glass co-doped with 1 mol% Yb2O3:0.5 mol% Ho2O3. As a result of the optical pumping at the wavelength of 976 nm in the produced optical fiber, strong and narrow band of amplified spontaneous emission (ASE) around 2.1 μm, corresponds to the 5I7 → 5I8 transition, were obtained.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (62 K)Download as PowerPoint slideHighlights•Thermally stable 1Yb2O3:0.5Ho2O3 (mol%) doped antimony–silicate glass was made.•Strong luminescence at 1950 nm was achieved by phonon-assisted energy transfer.•Double-clad antimony–silicate optical fiber with off-set core was made.•Amplified spontaneous emission at 2.1 μm was attained in optical fiber.•The optical trapping of Ho3+ ions causes narrowing and red-shifting of ASE emission.