Spectral properties and stability of Er3+-doped TeO2-WO3 glass

Er3+-doped TeO2-WO3 glass was fabricated and characterized by absorption spectrum, fluorescence spectrum, Raman spectrum and stability. The Judd-Ofelt parameter ohm(t)(t = 2, 4, 6) were calculated from the absorption spectrum by the Judd-Ofelt theory. The fluorescence spectrum indicates that the fluorescence width at half-maximum (FWHM) is 66nm. The stimulated emission cross-section of Er3+ in TeO2-WO3 glass at 1532 nm was calculated to be 0.80 x 10(-20) cm(2) by McCumber theory. The phonon energy of TeO2-WO3 glass is found to be 931 cm(-1). The difference between crystallization onset temperature and glass transition temperature Delta T is 112 degrees C. These results show that Er3+-doped TeO2-WO3 glass has higher stability and good spectral properties, which were useful for broadband amplifier. (c) 2005 Elsevier B.V. All rights reserved.

Spectroscopic properties and thermal stability of Er3+-doped tungsten-tellurite glass for waveguide amplifier application

Tungsten-tellurite glass with molar composition of 60TeO(2)-30WO(3)-10Na(2)O has been investigated for developing planar broadband waveguide amplifier application. Spectroscopic properties and thermal stability of Er3+-doped tungsten-tellurite glass have been discussed. The results show that the introduction Of WO3 increases significantly the glass transition temperature and the maximum phonon energy. Er3+-doped tungsten-tellurite glass exhibits high glass transition temperature (377 degrees C), large emission cross-section (0.91 x 10(-20) cm(2)) at 1532 nm and broad full width at half maximum (FWHM), which make it preferable for broadband Er3+-doped waveguide amplifier application. (c) 2005 Elsevier B.V. All rights reserved.

Spectroscopic properties and thermal stability of Er3+/Yb3+-codoped fluorophosphate glasses

A comprehensive study on the thermal stability and spectroscopic properties of Er3+/Yb3+-codoped Al(PO3)(3)-based fluorophosphate glasses is reported of the 1.5μ m fibre amplifiers in this paper. From optical absorption spectra, the Judd-Ofelt parameters of Er3+ in the glasses and several important optical properties, such as the radiative transition probability, the branching ratio and the spontaneous emission probability, have been calculated by using Judd-Ofelt theory. The fluorophosphate glass exhibits broadband near-infrared emission at 1.53μ m with a full width at half-maximum over 63nm, and a large calculated stimulated-emission cross-section of 6.85 x 10(-21)cm(2).

Effect of CdF2 addition on thermal stability and upconversion luminescence properties in Tm3+-Yb3+ codoped oxyfluoride silicate glasses

Tm3+-Yb3+ codoped oxyfluoride silicate glasses suitable for upconversion laser has been fabricated. In this paper, effect of CdF2 addition on thermal stability and upconversion luminescence properties in Tm3+-Yb3+ codoped oxyfluoride silicate glasses have been systematically investigated. The experimental results indicate that, with the substitution CdF2 for PbF2, the glass thermal stability increases and the UV cutoff edge moves to short-wave band slightly. With increasing CdF2 content, the blue and red upconversion luminescence intensity increases slightly at first, and then increases rapidly. While the near infrared (NIR) upconversion emission intensity increases notably at first and then increases slightly. However, the blue and NIR luminescence intensity are much stronger than that of red, indicating these oxyfluoride silicate glasses are more preferable for blue and NIR emissions than red emission. The possible upconversion mechanisms for the blue, red and NIR fluorescence are also estimated and evaluated. (c) 2006 Elsevier B.V. All rights reserved.

UV-blue upconverted emission from Nd3+-doped InF3-based heavy-metal fluoride glasses for blue upconversion fibre laser

We report spectral properties and thermal stability of Nd3+-doped InF3-based heavy-metal fluoride glasses. Fluoroindate glasses in the chemical compositions (in mol%) of (38-x)InF3-16BaF(2)-20ZnF(2)-20SrF(2)-3GdF(3)-1GaF(3-)2NaF-xNdF(3) (x = 0.1, 0.5, 1, 2, 3) have been prepared under a controlled atmosphere in a dry box. Strong UVblue upconversion emission from a green excitation wavelength has been observed and the involved mechanisms have been explained. Near-infrared emission occurs simultaneously upon excitation of the UV-blue upconversion emissions with a cw Ar(+)laser. The upconversion spectra have revealed four dominant emissions at 354, 380, 412 and 449 nm, which belong to the transitions of D-4(3/2) -> I-4(9/2), D-4(3/2) -> I-4(11/2) and P-2(3/2) -> I-4(9/2), D-4(3/2) -> I-4(13/2) and P-2(3/2) -> I-4(11/2), D-4(3/2) -> I-4(15/2) and P-2(3/2) -> I-4(13/2), respectively.

Study on the hydrolytic property and thermal stability of LiAlO2 substrate

The hydrolytic property and thermal stability of LiAlO2 (LAO), important factors for its application, were examined by AFM and X-ray rocking curve. We found that H2O may be deleterious for LAO surface polishing when the root mean square (RMS) value is less than 1 nm. However, when the RMS value is more than 1 nm it may be useful for LAO polishing. (100)-plane LAO substrates are annealed in the range of 850-900 degrees C in flux N-2, Slick AlN layer probably is produced on the substrate surface. M-plane GaN layer has grown on the substrate by metal-organic chemical vapor deposition (MOCVD) method. Theses results show that LiAlO2 crystal is a promising substrate of fabricating high-efficiency LEDs by MOCVD. (c) 2006 Elsevier B.V. All rights reserved.