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We report on the realization of monolithic optical microcavities using a single wall carbon nanotubes doped polymer as active material. Thanks to the control of the polymer thickness, a fine control of the cavity mode energy is achieved, which allows to tune it in exact resonance with a specific chiral species emission line. The quality factor of the filled cavity mode (Q = 40) allows to selectively extract the luminescence of the (7,5) chiral species. Finally, angle resolved experiments show the tunability of the emission energy within a 150 meV range.

All-semiconductor plasmonic gratings are investigated by spectroscopic nanoimaging in the vicinity of the plasma frequency, where the material behaves as an epsilon near-zero (ENZ) material. Both phase-sensitive scattering type nanoscopy (s-SNOM) and photoinduced force microscopy (PiFM) are carried out on this structure. The obtained data and models reveal that PiFM, as for s-SNOM, can have a mostly dispersive line shape, in contrast with recent near-field spectra obtained with photothermal AFM nanoscopic imaging on ENZ material where absorption maxima are observed. On the obtained result, PiFM signal exhibited better sensitivity to the dielectric function variation while interferometric s-SNOM can provide additional phase information. Localized surface plasmon resonances (LSPR), highly confined on the structure edges were also observed with both techniques. A higher sensitivity was observed with PiFM for both dielectric contrast imaging and LSPR observation. In addition, for both microscopies, the near-field response is phenomenologically described using a similar formalism based on dipole-image dipole approach. In this model, the sensitivity difference between both techniques is mostly accounted for by probes having different polarizabilities.

Graphene physics and plasmonics are two fields which, once combined, promise a variety of exciting applications. One of those applications is the integration of active nano-optoelectronic devices in electronic systems, using the fact that plasmons in graphene are tunable, highly confined and weakly damped. A crucial challenge remains before achieving these active devices: finding a platform enabling a high propagation of Graphene Plasmons Polaritons (GPPs). Suspended graphene presenting ultrahigh electron mobility has given rise to increasing interest. We numerically studied the plasmonic properties of suspended graphene. We propose a hybrid configuration and a set of conditions to launch graphene plasmons via an in-plane gold nanoantenna, for micrometric propagation of surface plasmons in suspended graphene. Finally, we propose a realistic optoelectronic device based on the use of suspended graphene.