Orbital angular momentum (OAM) multiplexing in free-space optical data transfer

Abstract

In the optical wireless communication systems proposed by Gibson, et al 1 , the information is encoded as states of orbital angular momentum (OAM) of light and the transmitter unit can produce laser beam with single OAM-state in a timeslot. Recently we have proved that it is possible to generate multiple OAM-states simultaneously by single spatial light modulator 2 . This method is adopted in our free-space optical wireless communication system and these OAM-states can be detected in the receiving unit by a computer-generated hologram. Hence, the transmission capacity is enhanced significantly without increasing the complexity of system.

Aberration-insensitive twisted wavefront detection using polarization correlation

“…The OV beam carries an orbital angular momentum (OAM) of lℏ per photon [2]. The OAM states of vortex beam exhibit potential applications in information encoding and free space communication, particle trapping, and manipulation [3][4][5][6][7][8][9]. As OAM states of light beam possess an infinite number of eigenstates it provides a possibility to increase the transmitting capacity of the encoded information in information encoding [3].…”