Angular momentum of optical vortex arrays

Guided by the aim to construct light fields with spin-like orbital angular momentum (OAM), that is light fields with a uniform and intrinsic OAM density, we investigate the OAM of strictly periodic arrays of optical vortices with rectangular symmetry. We find that the OAM per unit cell depends on th...

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Detalles Bibliográficos
Autores: Courtial, Johannes, Zambrini, Roberta, Dennis, Mark R., Vasnetsov, Mikhail
Tipo de recurso: artículo
Fecha de publicación:2006
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/6062
Acceso en línea:http://hdl.handle.net/10261/6062
Access Level:acceso abierto
Palabra clave:Optics
Orbital angular momentum
Optical vortices, mechanics
Descripción
Sumario:Guided by the aim to construct light fields with spin-like orbital angular momentum (OAM), that is light fields with a uniform and intrinsic OAM density, we investigate the OAM of strictly periodic arrays of optical vortices with rectangular symmetry. We find that the OAM per unit cell depends on the choice of unit cell and can even change sign when the unit cell is translated. This is the case even if the OAM in each unit cell is intrinsic, that is independent of the choice of measurement axis. We show that spin-like OAM can be found only if the OAM per unit cell vanishes. Our results are applicable to the z component of the angular momentum of any x- and y-periodic momentum distribution in the xy plane, and can also be applied to other periodic light beams and arrays of rotating solids or liquids.