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Fermionic Chern insulator from twisted light with linear polarization

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 نشر من قبل Swati Chaudhary
 تاريخ النشر 2020
  مجال البحث فيزياء
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A Fermionic Chern insulator serves as a building block for a plethora of topological phases of matter. Chern insulators have now been realized by imposing magnetic order on topological insulators, in hexagonal arrays of helical waveguides, or by driving graphene or graphene-like optical lattices with circularly polarized light. It is known that light beams, in addition to spin angular momentum (SAM), can also carry orbital angular momentum (OAM). Such OAM beams are now being extensively used for new applications in a variety of fields which include optical communication, quantum information, cosmology, and attophysics. These beams are characterized by a phase singularity at the center. The possibility of impinging these beams to create Fermionic topological phases of matter that can harness the central phase singularity of an optical vortex beam has not yet been explored. Here, we propose how a linearly polarized OAM beam can be used to realize a Fermionic Chern insulator.

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