Fiber optic polarization beam splitter using a reduced graphene oxide-based interlayer

A fiber-optic polarization beam splitter (PBS) incorporating reduced graphene oxide (rGO) as a metallic interlayer material is proposed and demonstrated. It is experimentally shown that the polarization beam splitting function can readily be obtained using a coupler structure with a thin rGO layer embedded between two side-polished fibers due to induced transverse magnetic (TM) surface waves. The rGO layer was prepared by a simple method of dielectric GO spraying and ultraviolet irradiation-based reduction. The polarization extinction ratio of our implemented PBS was measured to be 14.5 dB at a wavelength of 1550 nm for both through- and cross-port. Its operating bandwidth was shown to be at least 100 nm (from 1500 to 1600 nm), which was limited by the maximum tuning range of the input tunable laser used.