Fig. 3: Chiral routing of spin-carrying photons.

a Simulated electric-field profile of the waveguide mode propagating along the line defect with a direction being determined by the spin state of the emitted photons from an embedded QD. The inset shows two transition dipole moments of \(\sigma ^ +\) and \(\sigma ^ -\) with orthogonal circular polarization. b Calculated directionality for circularly polarized dipoles as a function of position relative to the glide-plane waveguide structure. The degree of circular polarization of the internal electric field determined the chiral regions of the waveguide. Two local waveguide points of P1 and P2 represent extreme cases with zero directionality (linearly polarized light field) and pure circularly polarized light field (chiral point), respectively. c Optical measurement for QDs located in 6 different waveguides. The red and blue lines represent the photon collection from the left and right out-couplers, respectively. The Zeeman components of the QDs in an out-of-plane magnetic field of B = 3 T have opposite circular polarizations. The results indicate a strong chiral coupling of QDs into the waveguide mode.