【摘 要】
：
With the rapid growth of optical communications traffic,the demand for broadband optical amplifiers continues to increase.It is necessary to develop a gain medium that covers more optical communication bands.We precipitated PbS quantum dots[QDs]and BaF2 ∶
【机 构】
：
State Key Laboratory of Luminescent Materials and Devices,Guangdong Provincial Key Laboratory of Fib
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With the rapid growth of optical communications traffic,the demand for broadband optical amplifiers continues to increase.It is necessary to develop a gain medium that covers more optical communication bands.We precipitated PbS quantum dots[QDs]and BaF2 ∶ Tm3+ nanocrystals[NCs]in the same glass to form two independent emission centers.The BaF2 NCs in the glass can provide a crystal field environment with low phonon energy for rare earth[RE]ions and prevent the energy transfer between RE ions and PbS QDs.By adjusting the heat treatment schedule,the emission of the two luminescence centers from PbS QDs and Tm3+ ions perfectly splices and covers the ultra-broadband near-infrared emission from 1200 nm to 2000 nm with bandwidth over 430 nm.Therefore,it is expected to be a promising broadband gain medium for fiber amplifiers.
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