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Ce, Tb and Eu single and ternary doped borosilicate glasses were prepared and effect of Tb concentration on luminescence properties of ternary co-doped glasses were analyzed by utilizing emission spectra, excitation spectra, the Commission International de I'Eclairage (CIE) colorimetric system and fluorescence decay curves. The results show that Tb concentration significantly affects spectral intensities of ternary co-doped glasses when excited by near ultraviolet (NUV). With the increasing of Tb concentration, the blue emission of Ce is weakened and the red emission of Eu is slightly enhanced. Both the color coordinates and correlated color temperatures (CCTs) can be adjusted by Tb concentration. Besides, the energy transfers from Ce to Tb and from Tb to Eu were observed. Measured characteristic lifetimes of Tb indicate that the energy transfer from Ce to Tb tends to predominate in whole process. The studies show that Ce/Tb/Eu ternary doped borosilicate glasses might be promising luminescence materials for NUV pumped white LEDs. [ABSTRACT FROM AUTHOR]

Abstract: Eu2+/Dy3+ co-doped high silica glasses with different holding temperatures (T1) and the highest sintering temperatures (T2) were prepared. The emission spectra, infrared absorption spectra, and densities of glass samples show that T1 can greatly influence the shrinkage process of porous glass and T2 decides the residual content of OH groups in sintered samples, which are both important influencing factors on the luminescent properties. The Eu2+/Dy3+ co-doped high silica glass sintered at T1=800°C and T2=1000°C has the highest luminescent intensity for its least residual pores and OH groups. Besides, the theory of pore shrinkage was also referred to explain the experimental results. [Copyright &y& Elsevier]

Abstract: Luminescent properties of Ce/Tb/Eu co-doped calcium borosilicate glass were investigated through excitation and emission spectra, fluorescence lifetimes and colorimetric analysis. The spectra results show that the concentration quenching of Eu3+ ions occurs when the concentration of Eu2O3 ranges from 0.75mol% to 1.00mol% and Ce3+, Tb3+ and Eu2+ ions are all the donors which can transfer energy to Eu3+. It can be indicated from the analysis of lifetimes that through nonradiative transition, Tb3+ ions can accept energy from Eu2+ ions and also transfer energy to Eu3+ ions. Furthermore, the colorimetric analysis show that the correlated color temperatures (CCT) of Ce/Tb/Eu co-doped calcium borosilicate glass can be adjusted from cold white to warm white by controlling the concentration of Eu2O3. [Copyright &y& Elsevier]

• The anisotropic coherent perfect absorption effect of borophene is explored. • The absorption rate can achieve continuous all-optical modulation from 0.01 % to 99.95 % in telecommunications waveband. • The resonant wavelength of coherent perfect absorption can be active switched via simply adjusting the polarization angle of the incident light. • The maximum modulation depth can reach 1.64 × 104 and 2.33 × 104 for x - and y -polarization, respectively. This paper proposed a borophene-based metamaterial device to achieve the anisotropic coherent perfect absorption (CPA) effect in the two-port device. By simply adjusting the polarization angle of the incident light, the dynamic switching of the CPA resonance peak wavelength can be achieved. Besides, by simultaneously modulating the electron doping concentration of borophene and the relative phase of the incident light, the coherent absorption efficiency of borophene can be continuous modulated for both polarization directions. Furthermore, the theorem of scattering matrix is utilized to elucidate the physical mechanism of CPA, and the analytical results demonstrate remarkable accordance with the numerical computations. Owing to the flexible continuous tunability, the proposed borophene CPA device is expected to open up new opportunities for optical modulators and all-optical logic chips. [ABSTRACT FROM AUTHOR]

To obtain the quantitative doping amount of rare earth ions in high silica glass, the RE ions diffusing into pores and adsorbed on the surface of pores by ion-exchange were both considered and the theoretical model of the doping amount was established. The results show that the adsorption quantity of ion-exchange is only about one-tenth of diffusion fluxes. So to improve the doping amount of RE ions in high silica glass, increasing the doping solution concentration is the easiest way and increasing the specific surface area of porous glass is not an efficient method. The absorbance of sintered porous glasses with the different content of Ce 3+ and Sm 3+ were measured to prove the calculation results of doping amount, qualitatively. The results indicated that the absorbance of different samples grows in line with the doping amount trend. [ABSTRACT FROM AUTHOR]