飞秒激光照射下Yb^(2+)/Yb^(3+)共掺石英玻璃上转换荧光研究

Upconversion luminescence of the Yb^(2+)/Yb^(3+) co-doped silica glass with femtosecond laser irradiation

为了研究Yb2+在石英玻璃中的光谱特性,提出采用气炼法制备Yb^(2+)/Yb^(3+)共掺石英玻璃。首先对Yb^(2+)的形成过程进行了分析,然后对制备的Yb^(2+)/Yb^(3+)共掺石英玻璃的吸收特性和发射特性进行了分析。结果表明,所制备的Yb^(2+)/Yb^(3+)共掺石英玻璃在260、320、359、400和437nm紫外和可见光波长处以及在910和975nm近红外波长处均出现了吸收峰,并且在530nm可见波长处出现了发射峰;使用波长位于710nm的飞秒激光照射所制备的Yb^(2+)/Yb^(3+)共掺石英玻璃,观察到了位于500nm波长处左右的上转换荧光。分析表明,Yb^(2+)/Yb^(3+)共掺石英玻璃上转换荧光是两光子同时被Yb2+吸收所引起的。

In order to study the spectrum characteristics of Yb2＋ ions in the silica glass,the flame fusion process is put forward to prepare the Yb2＋/Yb3＋ co-doped silica glass. First of all,the forming process of Yb^2＋ ions in the adopted process is analyzed. The absorption characteristics and emission characteris- tics of the prepared Yb2＋/Yb3＋ co-doped silica glass are analyzed. The analysis results show that the prepared Yb2＋/Yb3＋ co-doped silica glass has absorption peaks in the ultraviolet （UV） and visible wavelengths of 260 nm,320 nm,359 nm,400 nm and 437 nm as well as the near infrared wavelengths of 910 um and 975 urn,and has the emission peak in the visible wavelength of 530 nrn. The upconversion luminescence around 500 nm is observed when the prepared Yb2＋/Yb3＋ co-doped silica glass is irradia- ted by the femtosecond laser. What＇s more, the production mechanism of the upconversion luminescence of the Yb2＋/Yb3＋ co-doped silica glass is analyzed. It is proved that the forming reason of the upconve- rsion luminescence is that two-photon is absorbed simultaneously by Y2＋ ions in the Yb2＋/Yh3＋ co- doped silica glass.