Optical loss induced by metal electrodes in a polymer optical waveguide for optical sensor

Optical electric field sensors have received significant attention in recent years for their potential in a broad range of applications. There are many literatures about the optical electric field sensors, but only a few reports focus on the optical losses. In this paper, an analysis model is developed for the design of the electrode of a polymer electro-optic modulator in an optical electric field sensor. The optical losses due to the electrode are presented for different core waveguide thickness and cladding refractive indices. It also had been found that the optical loss due to electrode absorption will depend not only on the cladding layer but also on the core waveguide thickness. At the same time, the thickness of the cladding layer and core waveguide can be chosen freely by adjusting the refractive index of the polymer materials and keeping the optical losses to be less than 0·1 dB/cm. The results will be helpful for the design of a polymer electro-optic modulator in an optical electric field sensor.