Coherent Surface Plasmon Hole Burning via Spontaneously Generated Coherence

Surface plasmon (SP)—induced spectral hole burning (SHB) at the silver-dielectric interface is investigated theoretically. We notice a typical lamb dip at a selective frequency, which abruptly reduces the absorption spectrum of the surface plasmons polaritons (SPP). Introducing the spontaneous generated coherence (SGC) in the atomic medium, the slope of dispersion becomes normal. Additionally, slow SPP propagation is also noticed at the interface. The spectral hole burning dip is enhanced with the SGC effect and can be modified and controlled with the frequency and intensity of the driving fields. The SPP propagation length at the hole-burning region is greatly enhanced under the effect of SGC. A propagation length of the order of 600 µm is achieved for the modes, which is a remarkable result. The enhancement of plasmon hole burning under SGC will find significant applications in sensing technology, optical communication, optical tweezers and nano-photonics.

Antenna surface plasmon emission by inelastic tunneling

Surface plasmons polaritons are mixed electronic and electromagnetic waves. They have become a workhorse of nanophotonics because plasmonic modes can be confined in space at the nanometer scale and in time at the 10 fs scale. However, in practice, plasmonic modes are often excited using diffraction-limited beams. In order to take full advantage of their potential for sensing and information technology, it is necessary to develop a microscale ultrafast electrical source of surface plasmons. Here, we report the design, fabrication and characterization of nanoantennas to emit surface plasmons by inelastic electron tunneling. The antenna controls the emission spectrum, the emission polarization, and enhances the emission efficiency by more than three orders of magnitude. We introduce a theoretical model of the antenna in good agreement with the results.

Theoretical study of liquid crystal dielectric-loaded plasmonic waveguide

A fully two-dimensional theoretical study of the electromagnetic wave propagation through Metal–Liquid Crystal–Metal (M–LC–M) waveguide structure is presented. Dispersion relations corresponding to both symmetric and antisymmetric-coupled surface plasmons polaritons modes in M–LC–M structure are derived and numerically solved. The effects of LC tilt angles on the effective refractive index and propagation length are proposed. The analytical method is in good agreement with those obtained from finite-difference time-domain simulation. The obtained analytic formula can be used as an efficient element in designing tunable ultrahigh nanoscale integrated plasmonic devices.