Alencar Márcio A R C, Maciel Glauco S, de Araújo Cid B, Patra Amitava
Departamento de Física, Universidade Federal de Alagoas, 57072-970, Maceió, AL, Brazil.
J Nanosci Nanotechnol. 2008 Dec;8(12):6564-8.
We investigated the frequency upconversion (UC) process in BaTiO3:Er3+ nanocrystals for excitation wavelengths in the range 638 to 660 nm. Green upconversion emissions at 526 and 547 nm corresponding to 2H11/2 --> 4I15/2 and 4S3/2 --> 4I15/2 to transitions of the Er3+ were observed. The excitation spectrum for UC emissions presented three bands, due to ground state and excited state absorption of Er3+ ions. The UC intensity as a function of the laser power was investigated and it was found this a two-photon absorption process.
我们研究了BaTiO₃:Er³⁺纳米晶体在638至660 nm范围内激发波长下的频率上转换（UC）过程。观察到对应于Er³⁺的²H₁₁/₂→⁴I₁₅/₂和⁴S₃/₂→⁴I₁₅/₂跃迁的526和547 nm处的绿色上转换发射。由于Er³⁺离子的基态和激发态吸收，UC发射的激发光谱呈现出三个波段。研究了UC强度作为激光功率的函数，发现这是一个双光子吸收过程。
