A new publication in Phys. Rev. A from the Reiter group
In photonics, a chiral emitter describes an emitter that couples differently to different polarizations of the light field. On the other hand, in a nano-photonic structure the polarization of the light field is position dependent. For example, in a wave guide, one can find points of pure circular polarization, so called C-points. Accordingly, the excitation of a chiral emitter depends sensitively on its placement. Interestingly, also the emission characteristic of the emitter is affected by the placement. If a chiral emitter is placed in the C-point of a wave guide, the emission is directed, i.e., the light propagates only to one direction. In this paper, we have developed a method to describe the coupled light-emitter system, where we considered a classic field described by a finite-difference-time-domain (FDTD) method coupled to a quantum emitter described within a density matrix formalism. We show that indeed the emission of the chiral emitter into a wave guide can go only right or only left. We further discuss the placement of a chiral emitter in the more sophisticated structure of an optical circulator, where we see that at each round the effect on the emitter is diminished. The results give interesting insights into the spatio-temporal dynamics of light fields in nanophotonic structures containing quantum emitters.
The paper results from a collaboration with the theoretical group from Sang Soon Oh from Cardiff University.