Negative dispersion: a backward wave or fast light? Nanoplasmonic examples.
Propagation of light in a negative dispersion regime (antiparallel phase and group velocities) may be attributed to either fast light or a backward wave. We show that by applying causality, only one of these is valid for each scenario. A nanoplasmonic structure is shown to support both types of solution depending on the parameters.
Feigenbaum
Eyal
E
Electrical Engineering Department, Technion, Haifa 32000, Israel.
Kaminski
Noam
N
Orenstein
Meir
M