Infrared (1.2-1.6 mu m) luminescence in Cr4+: Yb3Al5O12 single crystal with 940 nm diode pumping

Infrared (1.2-1.6 mu m) luminescence in a ytterbium aluminium garnet (YbAG) crystal, doped with Cr (0.05 at.%) ions, was investigated under CW laser diode pumping (lambda = 940 nm). The Cr4+ emission band was observed with its peak at 1.34 mu m and measured to be about 1.3 times with respect to Yb3+ IR luminescence (lambda = 1.03 mu m). We demonstrate that for the excitation wavelength of 940 nm Yb3+ ions act as sensitizers of the B-3(2)(T-3(2))-B-3(1)((3)A(2)) emission of Cr4+ ions. This crystal is promising as a high-efficient system for tunable laser (1.2-1.6 mu m) output. (c) 2004 Elsevier B.V. All rights reserved.

中国苔藓植物泥炭藓目至丛藓目6目的分类系统学研究

本项目在多个单位多位研究人员历尽艰辛，跋山涉水，调查采集大量的标本，并对中国苔藓植物标本进行整理和鉴定，进行多样性及分布格局分析，形成了中国苔藓植物泥炭藓目至丛藓目6目的分类系统体系，为苔藓植物的分类系统研究和今后学科的发展提供了科学的依据和材料。