【摘 要】
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The upconversion luminescences of YAlO3:Er3 phosphor co-doping with different Gd3 concentrations are investigated under the excitation of 980- and 532-nm diode lasers. A near ultraviolet upconversion emission at 410 nm is observed in YAlO3 under 532-nm
【出 处】
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ChineseOpticsLetters
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The upconversion luminescences of YAlO3:Er3 phosphor co-doping with different Gd3 concentrations are investigated under the excitation of 980- and 532-nm diode lasers. A near ultraviolet upconversion emission at 410 nm is observed in YAlO3 under 532-nm excitation. Moreover, the inactive Gd3 ions can improve the upconversion intensity efficiently in a certain range of concentration. Under 980-nm excitation, the visible upconversion emissions at 546 and 646 nm are enhanced by about 10 and 8 times at the Gd3 concentration of 40%, respectively. The upconversion emission at 410 nm under 532-nm excitation is also enhanced by 7 times. The substitution of Gd3 ions for Y3 sites changes the local symmetry of Er3 , leading to the improvement of upconversion efficiency.
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