‘Poynting vector optics’ for superdirective dimers

Analysis of instantaneous and time-average Poynting vector produced by a dimer of coupled meta-atoms is performed with the aim of providing insights into the formation of superdirective radiation by metamaterials. Visualisation of the superdirectivity is further supported by studies of the shape of causal surfaces separating the reactive and radiated power and their space-time diagrams.