Directing nanoscale optical flows by coupling photon spin to plasmon extrinsic angular momentum

Abstract

As any physical object, light undergoing a circular trajectory features a constant extrinsic angular momentum. Within strong curvatures, this angular momentum can match the spin momentum of a photon, thus providing the opportunity of a strong spin-orbit interaction. Using this effect, we demonstrate tunable symmetry breaking in the coupling of light in a curved nanoscale plasmonic waveguide. The helicity of the impinging optical wave controls the power distribution between the two counter-propagating guided modes, including unidirectional waveguiding. We found that up to 95 % of the incoupled light can be directed into one of the two propagation directions of the waveguide. This approach offers appealing new prospects for the development of advanced, deeply subwavelength optical functionalities.

References in corpus (6)

• Spin-orbit interactions of light
• Chiral nanophotonic waveguide interface based on spin-orbit coupling of light
• Conservation of Angular Momentum, Transverse Shift, and Spin Hall Effect in Reflection and Refraction of Electromagnetic Wave Packet
• Coriolis Effect in Optics: Unified Geometric Phase and Spin-Hall Effect
• Unidirectional sub-diffraction waveguiding based on optical spin-orbit coupling in subwavelength plasmonic waveguides
• Direct characterization of plasmonic slot waveguides and nanocouplers

Cited by in corpus (3)

• On-Chip Spin-Orbit Controlled Excitation of Quantum Emitters Coupled to Hybrid Plasmonic Nanocircuits
• On-chip detection of spin-selective routing in plasmonic nanocircuits
• A Spin-Optical Nano Device