Mode-selective photonic lanterns for orbital angular momentum mode division multiplexing

Abstract

We analyze the mode evolution in mode-selective photonic lanterns with respect to taper lengths, affected by possible mode phase differences varying along the taper. As a result, we design a three-mode orbital angular momentum (OAM) mode-selective photonic lantern by optimizing the taper length with mode crosstalk below -24 dB, which employs only one single mode fiber port to selectively generate one OAM mode.