Experimental characterization of a tuneable all-fiber mode converter device for mode-division multiplexing systems

Abstract

In this work, we present a novel scheme to make a controllable, stable, and versatile all-fiber mode converter device. The converter consists of a few modes polarization-maintaining fiber, which is laterally stressed using an electrical actuator. The electrical actuator provides a simple mechanism to control the refractive index changes in the optical fiber thought the elasto-optic phenomena. Thus, it is possible obtain a platform to make mode conversion between the HE₁₁ mode and the TE₀₁, TM₀₁ and HE₂₁ modes. Likewise, the proposed methodology allows controlling the modal conversion trough the variation of the applied force. The results reveal that the performance of the converter depends on the input light polarization, the analyzer angle and the applied force. In addition, the device presents a compact size of 8 cm and shows an excellent performance when is analyzed at 980 nm. Thereby, it is suitable to be implemented for future optical fiber communication systems that employs mode-division multiplexing.