超快激光对涂有量子点玻璃表面的微构造

基于金属量子点的局域等离激元效应,提出一种新的固体介质表面微结构的制备方法。利用飞秒激光辐照涂有Cu2S量子点的K9玻璃,在其表面制备出了类似光栅结构的亚波长周期性条纹。当飞秒激光的中心波长为1300 nm、脉宽为50 fs、激光功率为230 mW时,玻璃表面的亚波长周期性条纹结构尺寸为34 nm。通过模拟得到了附有Cu2S量子点玻璃表面的近场分布,模拟结果表明，出现这种周期性条纹结构是入射飞秒激光与量子点产生的等离激元场之间产生干涉引起的。该制备方法可以降低透明介质微构造的激光功率阈值,改善了透明基质表面的微纳结构加工工艺。

Ultrafast laser-induced formation of surface micro-structuring on quantum dot coated glass

The fabrication induced by ultrafast laser illumination on solid surface has been widely illustrated in the field of laser physics. A new nanoscale-structure fabrication method based on the local surface plasmon resonance of the quantum dots (QDs) which are adhered on the substrate is demonstrated. By illuminating a K9 substrate which has been coated by Cu2S QDs with femtosecond laser, a series of grating-like and sub-wavelength period strips are achieved. The interval between each strip is nearly 34 nm when the central wavelength, pulse duration and illumination power of the laser are 1300 nm, 50 fs and 230 mW respectively. Moreover, the mechanism of inducing period strips has been demonstrated by the simulated near field distribution of the adhered QDs on substrate. The result shows that the period strips result from the interference between femtosecond laser and localized plasmon induced by QDs. This preparation method can not only reduce the laser threshold of nanoscale-structure fabrication of transparent medium, but also improve the processing technology of the micro-nano structure on the surface of the transparent substrate.