Multi-beam and multi-mode orbital angular momentum by utilizing a single metasurface.
Opt Express
; 29(17): 27332-27339, 2021 Aug 16.
Article
em En
| MEDLINE
| ID: mdl-34615151
ABSTRACT
This paper proposes a novel metasurface that can simultaneously generate orbital angular momentum (OAM) beams with pre-designed different reflection directions, multi-beam and multi-mode under x-(y-) polarized terahertz wave incidence. The configuration of unit cell is made up of a hollow cross of Jesus structure as top layer, a PTFE substrate layer and a gold metal bottom plate. Theory of phase gradient distribution is derived and used to design multifunctional OAM metasurface. The proposed metasurface generates two OAM beams with OAM mode l = 1 and four OAM beams with l = -1 at frequency of 1 THz, respectively. Similarly, at frequency of 1.3 THz, the designed metasurface produces two OAM beams with l = -2 and an OAM beam with l = 2 for x-(y-) polarized wave incidence, respectively. Since each OAM mode can be used as an independent digital information coding channel, the designed multifunctional OAM metasurface has a wide application prospect in future terahertz communication.
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Base de dados:
MEDLINE
Idioma:
En
Revista:
Opt Express
Assunto da revista:
OFTALMOLOGIA
Ano de publicação:
2021
Tipo de documento:
Article