Patra Amitava, Ghosh Pushpal, Chowdhury Paramita Saha, Alencar Marcio A R C, Lozano B Whualkuer, Rakov Nikifor, Maciel Glauco S
Sol-Gel Division, Central Glass and Ceramic Research Institute, Jadavpur, Kolkata 700032, India.
J Phys Chem B. 2005 May 26;109(20):10142-6. doi: 10.1021/jp050685v.
The effect of dopant concentration on the blue upconversion (UPC) emission of Tm(3+) -doped ZrO(2) nanocrystals under different excitation wavelengths in the red region is reported. The UPC emissions are due to the f-f electronic transitions from excited states (1)G(4) and (1)D(2) of Tm(3+). We observed a chromatic change in the UPC with tuning the excitation wavelength. The UPC emission bands at 475, 488, and 501 nm are observed under excitation at 649 nm, but bands centered at 454 and 460 nm are observed when the excitation wavelength is tuned to 655 nm. The UPC emission could be tuned from 501 to 454 nm ( approximately 47 nm) by changing the excitation wavelength from 649 to 655 nm ( approximately 6 nm). The pump power dependence of the emission bands at 475, 488, and 501 nm were investigated on excitation intensity at 649 nm, and the emission bands at 454 and 460 nm are investigated on excitation intensity at 655 nm, which confirms that all of these UPC emission lines are a two-photon absorption process.
报道了掺杂浓度对红色区域不同激发波长下掺Tm(3+)的ZrO(2)纳米晶体蓝色上转换（UPC）发射的影响。UPC发射是由于Tm(3+)的激发态(1)G(4)和(1)D(2)的f-f电子跃迁。我们观察到随着激发波长的调整，UPC发生了颜色变化。在649nm激发下观察到475、488和501nm处的UPC发射带，但当激发波长调至655nm时，观察到以454和460nm为中心的发射带。通过将激发波长从649nm改变至655nm（约6nm），UPC发射可从501nm调至454nm（约47nm）。研究了649nm激发强度下475、488和501nm发射带的泵浦功率依赖性，以及655nm激发强度下454和460nm发射带的泵浦功率依赖性，这证实了所有这些UPC发射线均为双光子吸收过程。
