Abstract
We report on the fabrication and characterization of integrated Mach–Zehnder interferometers in polymer foil without an interaction window. The interferometers are based on inverted rib waveguides, which allow single mode behavior even for waveguide widths larger than a few micrometers. The phase change between the two interferometer arms upon a refractive index change of the analyte that serves as the upper cladding is generated by the asymmetricity of the two interferometer arms. A difference of the waveguide width in the straight part of the interferometer leads to different effective refractive indices and thus to a change in the interference signal. We show in small scale the process chain, which is compatible with a cost-effective roll-to-roll fabrication process. For a proof of principle we apply deionized water and a glucose solution as analytes to the sensor foils and detect the transmitted intensity as a measure of the induced phase change. A detection limit of refractive index units is reached for homogeneous sensing at a total system length of 9.3 mm and a total waveguide core thickness of 3 μm.
© 2016 Optical Society of America
Full Article | PDF ArticleMore Like This
Yanfen Xiao, Meike Hofmann, Ziyu Wang, Stanislav Sherman, and Hans Zappe
Appl. Opt. 55(13) 3566-3573 (2016)
Di Wu, Tao Zhu, Ming Deng, De-Wen Duan, Lei-Lei Shi, Jun Yao, and Yun-Jiang Rao
Appl. Opt. 50(11) 1548-1553 (2011)
Donghai Niu, Lilei Wang, Qiang Xu, Minghui Jiang, Xibin Wang, Xiaoqiang Sun, Fei Wang, and Daming Zhang
Appl. Opt. 58(5) 1276-1280 (2019)