188 resultados para Bi-material crack
Resumo:
A colorless transparent, blue green emission material was fabricated by sintering porous glass impregnated with copper ions. The emission spectral profile obtained from Cu+ -doped high silica glass (HSG) by 267-mn monochromatic light excitation matches that obtained by pumping with an 800-nm femtosecond laser, indicating that the emissions in both cases come from an identical origin. The upconversion emission excited by 800-nm femtosecond laser is considered to be a three-photon excitation process. A tentative scheme of upconverted emission from Cu+ -doped HSG was also proposed. The glass materials presented herein are expected to find application in lamps, high density optical storage, and three-dimensional color displays.
Resumo:
We report near infrared broadband emission of bismuth-doped barium-aluminum-borate glasses. The broadband emission covers 1.3 mum window in optical telecommunication systems. And it possesses wide full width at half maximum (FWHM) of similar to 200nm and long lifetime as long as 350 mus. The luminescent properties are quite sensitive to glass compositions and excitation wavelengths. Based on energy matching conditions, we suggest that the infrared emission may be ascribed to P-3(1) --> P-3(0) transition of Bi+. The broad infrared emission characteristics of this material indicate that it might be a promising candidate for broadband optical fiber amplifiers and tunable lasers. (C) 2005 Optical Society of America.
Resumo:
Broadband infrared luminescence covering the optical telecommunication wavelength region of 0, E and S bands was observed in GeO2: Bi, M (M = Ga, B) glasses prepared by conventional melting-quenching technique. The luminescence with a maximum at around 1320 nm possesses a full width at half maximum larger than 300 nm and mean fluorescent lifetime longer than 500 mus when excited by an 808 nm-laser. These glasses may have potential applications in widely tunable laser and super-broadband optical amplifier for the optical communications. (C) 2005 Elsevier B.V. All rights reserved.
Resumo:
最近,一种新型的掺铋发光材料引起了人们的关注。这种发光材料有长的荧光寿命(τ>200μs),在800nm激光激发下发射波长在1200~1600nm区间的超宽带荧光(荧光半高宽FWHM>200nm),其发光性质与以往文献中报道的Bi^3+或Bi^2+掺杂的发光材料的性质截然不同;光发射截面(σem)是光掺铒光纤放大器玻璃(EDFAG)的2~3倍,其σem×FWHM值是EDFAG的10倍左右,σem×τ值是掺Ti^3+蓝宝石的3倍左右。