Evaluation of a photonic lantern spatial demultiplexer based receiver for optical communication

TL;DR

This paper introduces a novel method to evaluate photonic lanterns for free space optical communication, demonstrating improved coupling efficiency and potential for compact receiver design through both numerical and experimental analysis.

Contribution

It presents a new modal decomposition-based evaluation method and compares photonic lanterns to traditional demultiplexers, showing advantages in efficiency and size.

Findings

Photonic lanterns outperform traditional demultiplexers in coupling efficiency for low order modes.

The numerical evaluation method accurately predicts experimental results.

Photonic lanterns enable significant size reduction in optical receivers.

Abstract

In this paper, we present a method based on a modal decomposition to quantify the efficiency of photonic lanterns (PL) based free space optical (FSO) communication receivers. We fabricate a seven port PL and we evaluate numerically the free space to fiber coupling efficiency based on a reconstruction of the fields at the PL FSO multimode port. We validate the numerical approach with an experimental characterization of the PL. Then we compare the PL to a commercial multiplane light converter spatial demultiplexer. The PL shows better coupling efficiency for low order spatial modes with orders of magnitude of demultiplexer size reduction. Finally we evaluate the PL receiver with a simulation of received optical wavefront in a FSO communication