New and distinct physical and chemical properties of matter emerge on the nanoscale when the structure size of the material becomes comparable to the mean-free path of the electrons or the scattering length-scale of phonons. The research in our group is centered around the development of nano-optical spectroscopies that enable both nanometer spatial and femosecond temporal resolution.
 |
| Light scattering and scanning of a sharp metal tip
illuminated by a
focused laser source: Sample contrast and resolution are obtained by
means of the locally enhanced tip-sample interaction spatially confined
by the tip apex radius. This allows for spatially resolved probing of
the linear (ω, e.g., IR-vib), inelastic (ω
− Δ, e.g., Raman), or
nonlinear (nω,
e.g., SHG)
optical response of
the sample with nanometer spatial and femtosecond temporal resolution. |
The optical antenna properties of metallic nanostructures allow one to concentrate and locally enhance optical fields to nanometer dimensions. This can be explored and applied for scanning probe optical near-field microscopy with nanometer spatial and femtosecond temporal resolution and sensitivity down to the single molecule level. Being compatible with a broad range of optical spectroscopies including time-resolved and nonlinear methods, we are making use of the technique for a broad range of applications including the in situ study of supramolecular, biomolecular and copolymer nanostructures, the nanomanipulation of optical molecular switches, tuning the local optical coupling in molecular plasmonics and optical antenna geometries, or probing correlation phenmena in multiferroic or other quantum many body systems.