Plasmon modes in graphene are influenced by the unusual dispersion relation of the material. For bulk plasmons this results in a n1/4 dependence of the plasma frequency on the charge density, as opposed to the n1/2 dependence in two-dimensional electron gas (2DEG); yet, bulk plasmon dispersion in graphene follows a similar q1/2 behavior as for other two-dimensional materials. In this work we co...

Graphene plasmons provide a suitable alternative to noble-metal plasmons because they exhibit much tighter confinement and relatively long propagation distances, with the advantage of being highly tunable via electrostatic gating. Here, we propose to use graphene plasmons as a platform for strongly enhanced light-matter interactions. Specifically, we predict unprecedented high decay rates of qu...

The low-frequency electronic excitations in double-walled armchair carbon nanotubes are studied within the random-phase approximation. The intertube atomic overlaps significantly affect the low-energy bands and thus enrich the low-frequency single-particle excitations and collective excitations. They induce more plasmon modes, reduce the plasmon strength, and change acoustic plasmons into optic...

We study the polarization dependence of surface-enhanced Raman scattering (SERS) in coupled gold nanoparticle-nanowire systems. The coupling between the continuous nanowire plasmons and the localized nanoparticle plasmons results in significant field enhancements and SERS enhancements comparable to those found in nanoparticle dimer junctions. The SERS intensity is maximal when the incident ligh...

We propose and demonstrate a novel type of coupling between polarons in a conjugated polymer and localized surface plasmons in infrared (IR) nanoantennas. The near-field interaction between plasmons and polarons is revealed by polarized photoinduced absorption measurements, probing mid-IR polaron transitions, and infrared-active vibrational modes of the polymer, which directly gauge the density...

The propagation of laser-excited surface plasmons along a gold film with surface roughness is directly observed via scattered light. The attenuation length of surface plasmons in a broad wavelength interval is calculated for smooth gold and silver films. The surface roughness, which was characterized with an AFM, introduces corrections to the attenuation length, angular dependence of the surfac...

A radio ”colour–colour” diagram is defined in order to determine the evolutionary state of synchrotron-emitting plasma bubbles that are ejected during outbursts in microquasars. We establish the colour–colour diagram for the plasmons of SS433 observed on 18 April 1998 using VLBI observations. We show that the radio plasmons are not consistent with a simple expanding sphere of plasmon. This may ...

The coincidence in excitation energy between surface plasmons on silver and the GaN band gap is exploited to couple the semiconductor spontaneous emission into the metal surface plasmons. A 3-nm InGaN/GaN quantum well ~QW! is positioned 12 nm from an 8-nm silver layer, well within the surface plasmon fringing field depth. A spectrally sharp photoluminescence dip, by a factor '55, indicates that...

We report on theoretical investigation of graphene based Field Effect Transistor (FET) structures for resonant absorption of terahertz (THz) radiation by the plasmons excited in the high sheet concentration and high carrier mobility active layers. Metallic grating gates with varying periods were used to couple the THz radiation into the plasmons in the active region of the devices. Such grating...

Interactions between absorbers and plasmonic metasurfaces can give rise to unique optical properties not present for either of the individual materials and can influence the performance of a host of optical sensing and thin-film optoelectronic applications. Here we identify three distinct mode types of absorber-coated plasmonic metasurfaces: localized and propagating surface plasmons and a prev...