Miyaji Godai, Miyazaki Kenzo
Opt Express. 2016 Mar 7;24(5):4648-4653. doi: 10.1364/OE.24.004648.
We demonstrate the formation of a homogeneous nanograting with 50-nm period on GaN in air, using ultraviolet femtosecond (fs) laser pulses at 266 nm in the recently developed two-step ablation technique. The experimental results have shown that the ablation technique successfully controlled the spatial mode of surface plasmon polaritons (SPP) excited on the target surface and decreased the grating period in accordance with the short wavelength of fs laser pulses. Calculation for a model target reproduces well the laser-wavelength dependent periods, being in good agreement with the observed, and supports the mechanism for nanostructuring.
我们利用最近开发的两步烧蚀技术，在空气中使用266nm的紫外飞秒（fs）激光脉冲，在GaN上展示了周期为50nm的均匀纳米光栅的形成。实验结果表明，该烧蚀技术成功地控制了在目标表面激发的表面等离激元极化激元（SPP）的空间模式，并根据fs激光脉冲的短波长减小了光栅周期。对模型目标的计算很好地再现了与激光波长相关的周期，与观察结果吻合良好，并支持了纳米结构化的机制。
