Infrared and visible luminescence properties of Er[sup 3+] and Yb[sup 3+] ions codoped Ca[sub 3]Al[sub 2]Ge[sub 3]O[sub 12] glass under 978 nm diode laser excitation.

Er[sup 3+] and Yb[sup 3+] ions codoped calcium aluminum germanate glass has been synthesized by solid-state reaction. An intense infrared emission at 1534 nm, which corresponds to the minimum losses of silica based fibers used in optical communications, and visible emissions at 416, 490, 525, 548, and 660 nm, corresponding to the [sup 4]I[sub 13/2]→[sup 4]I[sub 15/2], [sup 2]H[sub 9/2]→[sup 4]I[sub 15/2], [sup 4]F[sub 7/2]→[sup 4]I[sub 15/2], [sup 2]H[sub 11/2]→[sup 4]I[sub 15/2], [sup 4]S[sub 3/2]→[sup 4]I[sub 15/2], and [sup 4]F[sub 9/2]→[sup 4]I[sub 15/2] transitions of Er[sup 3+] ions, respectively, were simultaneously observed in this glass under the excitation of a 978 nm diode laser at room temperature. These emissions are mainly attributed to energy transfer from Yb[sup 3+] ions to Er[sup 3+] ions. The up-conversion processes involve a sequential two-photon absorption for the red (660 nm), the green emissions (525 and 548 nm) and the blue emission (490 nm), and a sequential three-photon absorption for the violet-bluish emission (416 nm). The up-conversion fluorescence of Ca[sub 3]Al[sub 2]Ge[sub 3]O[sub 12]:Er,Yb glass can be used to detect 980 nm infrared laser light. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]