Spectroscopic properties of Tm3+ doped TeO2-R2O-La2O3 glasses for 1.47 μm optical amplifiers

Upon excitation at 808 nm laser diode, an intense 1.47 mu m infrared fluorescence has been observed with a broad full width at half maximum (FWHM) of about 124 nm for the Tm3+-doped TeO2-K2O-La2O3 glass. The Judd-Ofelt parameters found for this glass are: Omega(2)= 5.26x 10(-20) cm(2), Omega(4) = 1.57 X 10(-20) cm(2) and Omega(6) = 1.44x 10(-20) cm(2). The calculated emission cross-sections of the 1.47 mu m transition are 3.57 x 10(-21) cm(2), respectively. It is noted that the gain bandwidth, sigma(c) x FWHM, of the glass is about 440 x 10(-28) cm(3), which is significantly higher than that in ZBLAN and Gallate glasses, a high gain of 35.5 dBat 1470 nm can be obtained in a TKL glass fiber. TeO2-R2O (R= Li, Na, K)-La2O3 glasses has been considered to be more useful as a host for broadband optical fiber amplifier. (C) 2011 Elsevier B.V. All rights reserved.