Bérubé Jean-Philippe, Frayssinous Clément, Lapointe Jérôme, Duval Simon, Fortin Vincent, Vallée Réal
Opt Express. 2019 Oct 14;27(21):31013-31022. doi: 10.1364/OE.27.031013.
A detailed study of photo-inscribed optical waveguides in PMMA and polycarbonate using a mid-IR laser is presented. The wavelength of the laser is tuned near the absorption peaks of stretching C-H molecular bonds and the focused beam is scanned onto the surface of planar polymer samples. For the first time, we report the formation of optical waveguides in both polymers through resonant absorption of the laser beam. The optical properties of the waveguides were thoroughly assessed. An elliptic Gaussian mode is guided at the surface of both polymers. Insertion losses of 3.1 dB for a 30 mm long on-surface waveguide inscribed in PMMA were recorded. Such waveguides can interact with the external medium through evanescent coupling. As a proof of concept, the surface waveguides are used as highly sensitive refractometric sensors. An attenuation dynamical range of 35 dB was obtained for a liquid that matches the index of the PMMA substrate. Our results pave the way for large scale manufacturing of low cost biocompatible photonic devices.
本文介绍了一项使用中红外激光对聚甲基丙烯酸甲酯（PMMA）和聚碳酸酯中的光写入光波导进行的详细研究。激光波长调谐至接近C-H分子键拉伸吸收峰附近，并将聚焦光束扫描到平面聚合物样品表面。我们首次报道了通过激光束的共振吸收在两种聚合物中形成光波导。对波导的光学特性进行了全面评估。在两种聚合物表面均引导了椭圆高斯模式。记录到在PMMA中写入的30 mm长表面波导的插入损耗为3.1 dB。此类波导可通过倏逝耦合与外部介质相互作用。作为概念验证，表面波导用作高灵敏度折射传感器。对于与PMMA衬底折射率匹配的液体，获得了35 dB的衰减动态范围。我们的结果为大规模制造低成本生物相容性光子器件铺平了道路。
