高等学校化学研究 ›› 2012, Vol. 28 ›› Issue (2): 295-298 .
QIAN Yan-nan, WANG Rui, XING Li-li, XU Yan-ling, YANG Chun-hui
QIAN Yan-nan, WANG Rui, XING Li-li, XU Yan-ling, YANG Chun-hui
摘要: The effect of Zn2+ ions codoped on the upconversion emission of Er3+ ions in Er:LiNbO3 crystal under different excitation wavelength was reported. The upconversion emission spectra of Zn/Er:LiNbO3 following 800 nm excitation reveal an enhanced green emission and a suppressed red emission simultaneously. The cross relaxation processes(2H11/2+4I13/2→4I11/2+4F9/2 and 4F7/2+4I11/2→4F9/2+4F9/2) are responsible for populating the red 4F9/2 emitting state. The dissociation effect of Zn2+ ions on the Er3+ cluster sites makes these cross relaxation processes inefficient. Under 980 nm excitation, the Zn2+ codoped leads to the decreased intensities of green and red upconversion emissions. These reductions are attributed to the inefficient cross relaxation processes(4I11/2+4I11/2→4F7/2+4I15/2 and 4F7/2+4I11/2→4F9/2+4F9/2) caused by the same dissociation effect of Zn2+ ions.