摘要
The effect of Zn 2＋ ions codoped on the upconversion emission of Er 3＋ ions in Er：LiNbO 3 crystal under different excitation wavelength was reported.The upconversion emission spectra of Zn/Er：LiNbO 3 following 800 nm excitation reveal an enhanced green emission and a suppressed red emission simultaneously.The cross relaxation processes（2 H11/2 ＋ 4 I13/2 → 4 I11/2 ＋ 4 F9/2 and 4 F7/2 ＋ 4 I11/2 → 4 F9/2 ＋ 4 F9/2） are responsible for populating the red 4 F 9/2 emitting state.The dissociation effect of Zn2＋ ions on the Er 3＋ cluster sites makes these cross relaxation processes inefficient.Under 980 nm excitation,the Zn 2＋ codoped leads to the decreased intensities of green and red upconversion emissions.These reductions are attributed to the inefficient cross relaxation processes（4 I11/2 ＋ 4 I11/2 → 4 F7/2 ＋ 4 I15/2 and 4 F7/2 ＋ 4 I11/2 → 4 F9/2 ＋ 4 F9/2） caused by the same dissociation effect of Zn 2＋ ions.
The effect of Zn 2＋ ions codoped on the upconversion emission of Er 3＋ ions in Er：LiNbO 3 crystal under different excitation wavelength was reported.The upconversion emission spectra of Zn/Er：LiNbO 3 following 800 nm excitation reveal an enhanced green emission and a suppressed red emission simultaneously.The cross relaxation processes（2 H11/2 ＋ 4 I13/2 → 4 I11/2 ＋ 4 F9/2 and 4 F7/2 ＋ 4 I11/2 → 4 F9/2 ＋ 4 F9/2） are responsible for populating the red 4 F 9/2 emitting state.The dissociation effect of Zn2＋ ions on the Er 3＋ cluster sites makes these cross relaxation processes inefficient.Under 980 nm excitation,the Zn 2＋ codoped leads to the decreased intensities of green and red upconversion emissions.These reductions are attributed to the inefficient cross relaxation processes（4 I11/2 ＋ 4 I11/2 → 4 F7/2 ＋ 4 I15/2 and 4 F7/2 ＋ 4 I11/2 → 4 F9/2 ＋ 4 F9/2） caused by the same dissociation effect of Zn 2＋ ions.
基金
Supported by the National Natural Science Foundation of China(No.10732100)
the Natural Science Foundation of Heilongjiang Province of China(No.B200903)
