Ultrafast nonlinear optical response of metallic nanostructures: Collective effects and hybrid materials

• Applicant: Professor Dr. Stefan Linden
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas ; Theoretical Condensed Matter Physics
• Term: from 2012 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 223324884

Particle plasmons, i.e. coherent excitations of the conduction band electrons, govern the optical properties of metallic nanostructures in the visible and in the near-infrared spectral region. Excitation of these particle plasmons with ultrashort light pulses gives can give rise to a spatiotemporal concentration of the electromagnetic field in the vicinity of the metallic nanostructure. The intensity in these „hot spots“ can exceed the incident intensity by orders of magnitude. In this project, we will investigate the ultrafast nonlinear optical response of metallic nanostructures. At this, we will concentrate on two aspects. The first subproject is devoted to collective effects in periodic metal nanoparticle arrays and complex metallic nanostructures containing several tightly packed particles. Here, we will study how the electromagnetic interaction between the particles modifies the nonlinear optical response of the ensemble. In the second subproject, we will investigate hybrid nonlinear optical materials composed of a metallic nanostructure and a dielectric nonlinear optical nanoparticle. We will combine the spatiotemporal „hot spots“ in the metallic nanostructure with the large nonlinear optical susceptibility provided by the nanoparticles in order to obtain an efficient nonlinear response even for moderate pulse intensities.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1391: Ultrafast Nanooptics
• Major Instrumentation: Triple grating imaging spectrograph
• Instrumentation Group: 1820 Nah-Infrarot-Spektralphotometer