This paper reports a systematic analysis on the upconversion fluorescence from a Nd3+-doped LaF3 planar waveguide grown on (111) oriented CaF2 substrates by molecular beam epitaxy. A spectroscopic study of upconversion emission has been carried out at low temperature. Upon infrared excitation into the H-2(9/2), F-4(5/2), or F-4(3/2) multiplets of Nd3+, strong uv upconversion emissions originating from D-4(3/2) to I-4(J) (J = 9/2, 11/2, and 13/2) transitions by a three-photon process have been observed. In addition, other upconversion emissions in the green and orange regions due to two-photon processes were also obtained and attributed to the (4)G(7/2) -->I-4(9/2), (2)G(7/2) + (4)G(5/2) --> I-4(9/2), and (4)G(7/2) --> I-4(11/2) transitions, respectively. In accordance with our experimental results, two kinds of energy-transfer processes are proposed as upconversion mechanisms responsible for the different emissions, and which are supported by a rate-equation analysis. The green and orange upconversions originate from an energy-transfer process involving two Nd3+ ions excited in the F-4(3/2) state. For the three-photon upconversion, two successive energy cross-relaxation are suggested to populate the D-4(3/2) level. The concentration dependence study has shown that the optimum concentration for a Nd3+ dopant is about 1 at. % for all the upconversion emissions. Owing to a guided configuration, upconversion emissions that are hardly detectable in a nonguided configuration at temperature higher than 100 K have now been recorded at room temperature.
Zhang X.,Serrano C.,Daran E.,et al. Infrared-laser-induced upconversion from Nd3+: LaF3 heteroepitaxial layers on CaF2(111) substrates by molecular beam epitaxy[J]. Physical Review B,2000,62(7):4446-4454.
APA
Zhang X.,Serrano C.,Daran E.,Lahoz F.,Lacoste G.,&MunozYague A..(2000).Infrared-laser-induced upconversion from Nd3+: LaF3 heteroepitaxial layers on CaF2(111) substrates by molecular beam epitaxy.Physical Review B,62(7),4446-4454.
MLA
Zhang X.,et al."Infrared-laser-induced upconversion from Nd3+: LaF3 heteroepitaxial layers on CaF2(111) substrates by molecular beam epitaxy".Physical Review B 62.7(2000):4446-4454.
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