Transparent glass ceramics containing Li2ZnSiO4:Cr4+ nanocrystals are prepared and their optical properties are investigated. The glass ceramics show intense broadband infrared luminescence and long fluorescence lifetime of about 90 μs. The single-pass optical amplification is demonstrated on a traditional two-wave mixing configuration. The optical gain efficiency is about 1.27 cm−1 when the excitation power is 0.80 W. The optical gain shows the similar wavelength dependence with luminescence properties. The transparent glass ceramics containing Li2ZnSiO4:Cr4+ nanocrystals have potential application as broadband gain media in optical communication system.

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Y(2)O(3): Eu(3+) nanofibers with the average diameter of ~300 nm were in situ fabricated by electrospinning. X-ray diffraction (XRD) pattern confirmed that the Y(2)O(3): Eu(3+) nanofibers were composed of pure body-centered cubic (bcc) Y(2)O(3) phase. High-resolution transmission electron microscopy (HRTEM) results indicated that Y(2)O(3): Eu(3+) nanofibers were constituted of nonspherical crystalline grains, and these crystalline grains were orderly arranged along the axial direction of single nanofiber. These Y(2)O(3): Eu(3+) nanofibers showed a partially polarized photoluminescence (PL). The arrangement of crystalline grains and the mismatch of dielectric constant between Y(2)O(3): Eu(3+) nanofiber and its environment probably contributed together to the polarized PL from Y(2)O(3): Eu(3+) nanofiber.

One-dimensional TiO 2 :xSm 3+ microfibers and microbelts were prepared by electrospinning. X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray spectrometer (EDS), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL), electron paramagnetic resonance (EPR), and polarized luminescence measurements were performed to characterize these TiO 2 :xSm 3+ microfibers and microbelts. SEM and HRTEM results indicate that TiO 2 :xSm 3+ microfibers calcined at different temperature are belt-like. The average width and thickness of TiO 2 :xSm 3+ microbelts calcined at 700 °C is about 1.0 and 0.4 µm, respectively. Under ultraviolet excitation (λ ex ) 330 nm) and commercial 365 nm UV lamp excitation, these TiO 2 :xSm 3+ microbelts show intense 4 G 5/2 f 6 H 5/2,7/2,9/2 emissions of Sm 3+ ions. Polarized luminescence measurement confirms that the luminescence of single TiO 2 :xSm 3+ microbelt is linear polarization.