MODE DIVISION MULTIPLEXER, MODE DIVISION MULTIPLEXING SYSTEM, DE-MULTIPLEXING SYSTEM, AND COMMUNICATION SYSTEM

摘要

The present application provides a mode division multiplexer, a mode division multiplexing system and a de-multiplexing system comprising the mode division multiplexer, and a communication system comprising the mode division multiplexing system and the de-multiplexing system. The mode division multiplexer comprises a hypersurface having multiple electromagnetic resonance units having a subwavelength and arranged in an array. The electromagnetic resonance unit is configured to perform phase modulation on a light beam transmitted to the electromagnetic resonance unit, so as to convert a spatial mode order of the light beam. Because the electromagnetic resonance unit has a subwavelength dimension and the dimension is smaller than a pixel dimension of a spatial light modulator in the prior art, different spatial modes subjected to phase modulation of the mode division multiplexer are low in crosstalk, so that the crosstalk is low when light beams in different spatial modes are multiplexed into a few-mode/multi-mode optical fiber. Furthermore, compared with the problem of polarization dependence of the spatial light modulator in the prior art, the mode division multiplexer of the present application can achieve polarization-independent phase modulation.