Incoherent and coherent manipulation of surface plasmon hole burning

Abstract

We theoretically investigate the spectral hole burning of surface plasmon polaritons (SPPs) at an interface between rubidium (87Rb) atomic medium and silver. A typical Lamb dip can be observed at a certain frequency where the absorption of SPPs is suddenly reduced. By applying Kerr-type nonlinearity to the 87Rb atomic gas, the slope of dispersion becomes more normal and steeper. Under the effect of Doppler broadening, a group index of at the SPPs hole burning region is obtained and is further enhanced to with the application of Kerr-nonlinearity. Similarly, the propagation length of SPPs is increased at the hole burning region and is further enhanced with Kerr-nonlinearity. Further, we show that this nonlinear effect results in the enhancement of the phase shift from 0.02 to 1.5 radian at the hole burning region. These results may find important applications in nano-photonics, optical tweezers, photovoltaic devices and sensing technology.