The article of the team of dr inż. Anna Wróblewska in the prestigious Carbon journal

New hybrid materials could enable coupling between plasmons (collective electron oscillations) in metals and excitons (electron and hole bound states) in carbon nanotubes. The properties of hybrid materials do not only result from the individual contribution of their components, but also from the strong coupling that occurs when they are combined.

The newest work "Doping and plasmonic Raman enhancement in hybrid single walled carbon nanotubes with embedded gold nanoparticles" presents the development of a material in the form of thin layers, where gold nanoparticles are embedded in the entire volume of the layer of carbon nanotubes. Until now, the literature describes only layered materials with a thin layer of nanoparticles on the surface of nanotubes. In this type of structure, free charge carriers derived from metallic nanoparticles are transferred to nanotubes, causing a doping effect manifested in changes in phonon energy and lifetime, scaling with the concentration of gold nanoparticles.

The publication presents a statistical analysis of Raman maps (allowing the study of large areas of the sample), which were correlated with the parameters of the characteristic bands: 2D and G. This allowed for a clear separation of the doping and stress effects in the hybrid layer. Then, the optical properties of the layers were investigated, showing that gold nanoparticles increase the efficiency of Raman scattering, and the gain is wavelength dependent. Moreover, the signal amplification over 3.5 times compared to the pure layer of carbon nanotubes was demonstrated. The shapes of the reinforced Raman profiles were interpreted using the fifth-order perturbation theory, taking into account the plasmonic effect.

The work was published in the renowned Carbon magazine (IF = 8,821, MEiN points: 140).