Chiral nanophotonic waveguide interface based on spin-orbit coupling of light

Understand

Controlling the flow of light by means of nanophotonic waveguides has the potential of transforming integrated information processing much in the same way that conventional glass fibers have revolutionized global communication.

• Owing to the strong transverse confinement of the light, such waveguides give rise to a coupling between the internal spin of the guided photons and their orbital angular momentum.
• Here, we employ this spin-orbit coupling of light to break the mirror symmetry of the scattering of light by a single gold nanoparticle on the surface of a nanophotonic waveguide.
• We thereby realize a chiral waveguide coupler in which the handedness of the incident light determines the direction of propagation in the waveguide.