Optical properties of three-dimensional plasmonic structures: Advanced methods and chirality

• Applicant: Professor Dr. Harald Giessen
• Subject Area: Theoretical Condensed Matter Physics
• Term: from 2010 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 179415757

• Final Report Year: 2014

Final Report Abstract

Within this project, we addressed several questions regarding the optical properties of stacked plasmonic nanostructures. On the one hand, we were working on advanced numerical and semianalytical approaches related to the Fourier modal method with adaptive coordinate transformations. On the other hand, we were developing and optimizing photonic devices with specific optical properties using our numerical expertise and simplifying models. The following subprojects have been carried out successfully: • Derivation of photonic eigenmodes: We have implemented an efficient scheme to determine photonic and plasmonic eigenmodes of nanostructures. • Coupling equations for stacked nanogratings: Based on the photonic eigenmodes of isolated nanogratings, we developed semi-analytical coupling equations in order to approximate the modes of stacked nanogratings and to gain more physical insight. • Implementation of magnetooptical materials: We extended our code to anisotropic material tensors, so that we are able to study magnetooptical materials. • Emission problem: Our numerical methods have been modified in order to include the emission of sources in the vicinity of nanoantennas, which has been used to study arrays of gold Yagi-Uda nanoantennas. • Plasmon ruler: In this project, we developed an ansatz to determine the position of plasmonic constituents in a reference frame by analyzing the far-field spectra. • Enhanced Faraday rotation: We have proposed and demonstrated a magnetooptical waveguide system with enhanced Faraday rotation due to the presence of plasmonic nanowires. • Mueller matrix analysis: Our numerical results have been converted to the Mueller matrix and compared with experimental results, revealing the spatial dispersion in plasmonic nanostructures, and showing that an effective medium approach must fail for describing these systems. • Chiral plasmonic structures: We gained fundamental insights in the chiral far-field and near-field response of plasmonic structures. Novel approaches for chiroptical spectroscopy have been proposed. Among the list of questions raised in the proposal, of course, not everything could be carried out successfully. Interestingly, it turned out too difficult to efficiently combine different coordinate transformations within one system to study rotated or helical chiral structures. Our publication on enhanced Faraday rotation has been presented in Nature Materials Research Highlight and Nature Photonics News and Views. Similarly, our article on the plasmon ruler, published in Science, has drawn a lot of attention.

Publications

• “Derivation of 3D plasmonic resonances in the Fourier modal method with adaptive spatial resolution and matched coordinates,” J. Opt. Soc. Am. A 28, 238-244 (2011)
  T. Weiss, N. A. Gippius, S. G. Tikhodeev, G. Granet, and H. Giessen
  
• “From near-field to far-field coupling in the third dimensions: Retarded interaction of particle plasmons,” Nano Lett. 11, 4421-4424 (2011).
  R. Taubert, R. Ameling, T. Weiss, A. Christ, and H. Giessen
  
• “Strong resonant mode coupling of Fabry-Perot and grating resonances in stacked two-layer systems,” Photonics and Nanostructures–Fundamentals and Applications 9, 390-397 (2011)
  T. Weiss, N. A. Gippius, G. Granet, S. G. Tikhodeev, R. Taubert, L. Fu, H. Schweizer, and H. Giessen
  
• “Towards 3d plasmon rulers,” Science 332, 1407-1410 (2011)
  N. Liu, A. P. Alivisatos, M. Hentschel, T. Weiss, and H. Giessen
  
• “Formation of chiral fields in a symmetric environment,” Optics Express 20, 26326-26336 (2012).
  M. Schaferling, X. Yin, and H. Giessen
  
• “Tailoring enhanced optical chirality: Design principles for chiral plasmonic nanostructures,” Phys. Rev. X 2, 031010 (2012)
  M. Schäferling, D. Dregely, M. Hentschel, and H. Giessen
  
• “Three-dimensional chiral plasmonic oligomers,” Nano Lett. 12, 2542-2547 (2012)
  M. Hentschel, M. Schäferling, T. Weiss, N. Liu, and H. Giessen
  
• “Interpreting chiral nanophotonic spectra: The plasmonic Born-Kuhn model,” Nano Lett. 13, 6238-6243 (2013)
  X. Yin, M. Schäferling, B. Metzger, and H. Giessen
  
• “Nonreciprocal plasmonics enables giant enhancement of thin-film Faraday rotation,” Nature Communications 4, 1599 (2013)
  J. Y. Chin, T. Steinle, T. Wehlus, D. Dregely, T. Weiss, V. I. Belotelov, B. Stritzker, and H. Giessen