Nonlinear finite-difference time-domain method for exciton-polaritons: Application to saltatory conduction in polariton neurons

Polariton neurons allow exciton-polaritons to transport information using a successive local switching in analogy to action potentials in biological neurons. The authors show here an analogue of saltatory conduction for enhancing signal speeds: by connecting bistable nodes with waveguides, polariton signal speeds can be increased tenfold. The modeling of this system requires a new theoretical tool: nonlinear finite-difference time-domain simulation, which accounts for the propagation of light in the full three-dimensional nanostructure together with nonlinear exciton-exciton scattering using Maxwell-Bloch equations.