Scottish Universities Physics Alliance (SUPA), School of Engineering and Physical Sciences, Department of Physics, Heriot-Watt University, Edinburgh, UK.
Opt Lett. 2012 Feb 15;37(4):491-3. doi: 10.1364/OL.37.000491.
We report the fabrication of high-strength (>30 dB) first order Bragg-grating waveguides in borosilicate glass substrates using ultrafast laser inscription. The cross section of each waveguide was controlled using the well known multiscan fabrication technique, where the desired waveguide cross section is constructed by scanning the sample through the laser focus multiple times. In order to fabricate high-strength gratings, it was therefore necessary to precisely control and spatially synchronize the refractive index modulations imprinted in the material by each scan. The Bragg-grating waveguides were inscribed using a femtosecond fiber laser that was externally modulated using an acousto-optic modulator. The required precision in the laser modulation was thus achieved by triggering the acousto-optic modulator using a position sensitive trigger signal supplied by the substrate translation stages themselves.
我们报告了使用超快激光刻写在硼硅酸盐玻璃衬底上制造高强度（>30dB）一阶布拉格光栅波导的方法。使用众所周知的多扫描制造技术控制每个波导的横截面，其中通过多次扫描穿过激光焦点来构建所需的波导横截面。为了制造高强度光栅，因此有必要精确控制和空间同步每个扫描在材料中产生的折射率调制。使用外部声光调制器对飞秒光纤激光器进行调制，从而刻写布拉格光栅波导。通过使用衬底平移台本身提供的位置敏感触发信号触发声光调制器，从而实现了激光调制所需的精度。
