Mode division multiplex communication technique based on dynamic volume hologram and phase conjugation

TLDR: In this article, the authors propose a mode division multiplex communication technique that can split a specific spatial mode in light from a spatial mode multiplexed in an optical fiber by fusion of a phase conjugation technique with spatial filtering processing by multiple-ed volume holograms and random diffusers.

Abstract: We propose mode division multiplex communication technique that can split a specific spatial mode in light from a spatial mode multiplexed in an optical fiber by fusion of a phase conjugation technique with spatial filtering processing by multiplexed volume holograms and random diffusers. In mode division multiplexing, the optical signal outgoing from the multimode optical fiber is in a condition that optical inform ation of plural spatial modes is overlapped, therefore it is difficult to de-multiplex electrically after light detection. Our technique enables to split it into each mode all optically and to compensate temporal modal shift dynamically. Mode de-multiplexing is realized by multiplexed holographic arithmetic device and phase matching of a wave surface for the spatial mode orthogonal to time. Therefore, if we use indices in conventional electronic processing, a very high-speed operation equivalent to that of 10-100PFLOPS can be realized without causing any delay in light information to be transmitted. Moreover, it can realize constructions of a system that can dynamically respond to temporal mode variations and distortions with fiber transmissions by using a photorefractive medium. Separating of around 60-70% was ach ieved in an experiment of separating three multiplexed spatial modes by controlling a volume type dynamic reconfigurable device based on LiNbO