Mode Signal Demultiplexer Design for Quantum OAM Electromagnetic Waves Transmission

Orbital Angular Momentum (OAM) is the new dimension of electromagnetic (EM) waves, which is discovered in recent years. The quantum OAM means that single photon of the EM waves has the intrinsic OAM. The quantum OAM waves have great potential for multiplexing transmission. Mode demultiplexer is necessary to implement the transmission system. However, the existing designs have serious drawbacks such as small separation distance and slow recognition speed. This makes a practical implementation of the quantum OAM transmission system challenging. Therefore, this paper proposes a practical mode demultiplexer design for the quantum OAM transmission system. The mode demultiplexer can separate the vortex electron beams with two OAM modes and increase the separation distance from μm to cm level. Moreover, it finally forms electrical signals to indicate the signal strength, which is not limited by the recognition speed. The demultiplexer can be used to realize a practical quantum OAM waves multiplexing transmission system.