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arXiv · 2212.00204

Pseudospin-2 in photonic chiral borophene

Philip Menz·Haissam Hanafi·Daniel Leykam·Jörg Imbrock·Cornelia Denz
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Abstract

Pseudospin is an angular momentum degree of freedom introduced in analogy to the real electron spin in the effective massless Dirac-like equation used to describe wave evolution at conical intersections such as the Dirac cones of graphene. Here, we study a photonic implementation of a chiral borophene allotrope hosting a pseudospin-2 conical intersection in its energy-momentum spectrum. The presence of this fivefold spectral degeneracy gives rise to quasiparticles with pseudospin up to $\pm2$. We report on conical diffraction and pseudospin-orbit interaction of light in photonic chiral borophene, which, as a result of topological charge conversion, leads to the generation of highly charged optical phase vortices.

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Philip Menz, Haissam Hanafi, Daniel Leykam, Jörg Imbrock, Cornelia Denz. 2022-12-01. Pseudospin-2 in photonic chiral borophene. https://doi.org/10.1364/prj.486916

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