Plasmonic nanostructure induced simultaneous slow and fast light propagation in a slab doped by four-level quantum dots

Abstract

The transmission and reflection properties of a pulse through a slab doped with quantum dots near a plasmonic nanostructure are investigated theoretically. It is found that by adjusting the distance between plasmonic nanostructure and dual quantum dots which is varied from 8.8 nanometer (nm) to 14.4 nanometer (nm) the transmission and reflection spectra for incident pulse through the slab can be modified. Furthermore, it is found that in the presence of plasmonic nanostructure, the reflected and transmitted pulses are completely phase dependent. Therefore, the group velocity of the reflected and transmitted pulses can be switched from slow to fast light by changing the phase difference of two laser fields.