Configurable TE- and TM-Pass Graphene Oxide-Coated Waveguide Polarizer
Wen-Yee Chong, Soon Xin Gan, Choon Kong Lai, Wu Yi Chong, Duk‐Yong Choi, Steve Madden, R.M. De La Rue, H. Ahmad
Abstract
A configurable optical waveguide polarizer using graphene oxide (GO) as a polarizing element has been demonstrated. The propagation characteristics of the GO-coated optical waveguide are changed from TM-pass to TE-pass by controlling the GO coating thickness in the sub-micron range during the deposition process. The highest extinction ratio measured for a TM-pass waveguide polarizer is 34.9 dB, using a coating length and thickness of 1.0 mm and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.34~\mu \text{m}$ </tex-math></inline-formula> respectively, while the highest extinction ratio measured for a TE-pass polarizer is 46.0 dB, using a coating length and thickness of 1.0 mm and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.71~\mu \text{m}$ </tex-math></inline-formula> respectively. The polarization extinction ratio has also been measured across the wavelength range from 1520 nm to 1620 nm - and a variation of less than 3.0 dB was obtained. Control of the coating thickness dependent characteristics of the GO-coated waveguides provides an avenue for tailoring of the polarization selection.