Electric control of spin orbit coupling in graphene-based nanostructures with broken rotational symmetry

TY - JOUR

T1 - Electric control of spin orbit coupling in graphene-based nanostructures with broken rotational symmetry

AU - Ciattoni , Alessandro

AU - Zayats, Anatoly

AU - Conti, Claudio

AU - Marini, Andrea

PY - 2020/7/21

Y1 - 2020/7/21

N2 - Spin and angular momenta of light are important degrees of freedom in nanophotonics which con-trol light propagation, optical forces and information encoding. Typically, optical angular momen-tum is generated using q-plates or spatial light modulators. Here, we show that graphene-supported plasmonic nanostructures with broken rotational symmetry provide a surprising spin to orbital an-gular momentum conversion, which can be continuously controlled by changing the electrochemical potential of graphene. Upon resonant illumination by a circularly polarized plane wave, a polygo-nal array of indium-tin-oxide nanoparticles on a graphene sheet generates scattered field carrying electrically-tunable orbital angular momentum. This unique photonic spin-orbit coupling occurs due to the strong coupling of graphene plasmon polaritons and localised surface plasmons of the nanoparticles and leads to the controlled directional excitation of graphene plasmons. The tuneable spin-orbit conversion pave the way to high-rate information encoding in optical communications, electric steering functionalities in optical tweezers, and nanorouting of higher-dimensional entangled photon states.

AB - Spin and angular momenta of light are important degrees of freedom in nanophotonics which con-trol light propagation, optical forces and information encoding. Typically, optical angular momen-tum is generated using q-plates or spatial light modulators. Here, we show that graphene-supported plasmonic nanostructures with broken rotational symmetry provide a surprising spin to orbital an-gular momentum conversion, which can be continuously controlled by changing the electrochemical potential of graphene. Upon resonant illumination by a circularly polarized plane wave, a polygo-nal array of indium-tin-oxide nanoparticles on a graphene sheet generates scattered field carrying electrically-tunable orbital angular momentum. This unique photonic spin-orbit coupling occurs due to the strong coupling of graphene plasmon polaritons and localised surface plasmons of the nanoparticles and leads to the controlled directional excitation of graphene plasmons. The tuneable spin-orbit conversion pave the way to high-rate information encoding in optical communications, electric steering functionalities in optical tweezers, and nanorouting of higher-dimensional entangled photon states.

M3 - Article

SN - 1863-8899

JO - Laser and Photonics Reviews

JF - Laser and Photonics Reviews

ER -