System investigations of few-mode erbium-doped fiber amplifier (FM-EDFA) for vortex mode amplifications

This paper describes the system performance of mode division multiplexing applications. The mode of amplification involved a ring profile-based multi-mode erbium-doped fiber amplifier with minimum support of 10 vortex spatial modes. The vortex modes are configured and generated by the vortex lens whose input is excited by a spatial laser source. The property of vortex modes can be processed with the linear combination of LP modes. The phase distribution of vortex modes has been twisted and the results achieved were spiral propagation in nature. Similar to the orbital angular momentum modes, the vortex mode is also part of the same group and offers minimal discrepancy among the higher-order modes. Following this approach, the proposed system promises efficient propagation of vortex modes at a higher data rate with minimum crosstalk and uniform gain distributions. The generated modes were classified as LP01, LP11, LP21, LP31, LP41, LP12, LP13, LP14, LP02, LP03 and their equivalent vortex modes were also investigated.