Metallic metamaterials have shown a number of fascinating properties over the last few years. A negative refractive index, negative refraction, superlenses, and optical cloaking are some of the ambitious applications where metamaterials hold great promise.

We are going to present fabrication methods for the manufacturing of 3D metamaterials [1]. We are investigating their coupling properties and the resulting optical spectra. Hybridization of the electric [2] as well as the magnetic [3] resonances allows us to easily understand the complex optical properties. Lateral as well as vertical coupling can result in EIT-like phenomena [4,5]. These phenomena allow to construct novel LSPR sensors with a figure of merit as high as five [6,7]. The connection between structural symmetry and their electric as well as magnetic dipole and higher-order multipole coupling will be elucidated. It turns out that stereometamaterials [8], where the spatial arrangement of the constituents is varied (see figure), reveal a highly complex rotational dispersion. The chiral properties are quite intriguing and can be explained by a coupled oscillator model [9].

We are going to give an outlook where complex plasmonic structures might be headed in the future.


References
[1] Na Liu, Hongcang Guo, Liwei Fu, Stefan Kaiser, Heinz Schweizer, and Harald Giessen: Three-dimensional photonic metamaterials at optical frequencies, Nature Materials 7, 31 (2008).
[2] N. Liu, H. Guo, L. Fu, S. Kaiser, H. Schweizer, and H. Giessen: Plasmon Hybridization in Stacked Cut-Wire Metamaterials, Advanced Materials 19, 3628 (2007)
[3] Na Liu, Liwei Fu, Stefan Kaiser, Heinz Schweizer, and Harald Giessen: Plasmonic Building Blocks for Magnetic Molecules in Three-Dimensional Optical Metamaterials, Advanced Materials 20, 3859 (2008).
[4] Na Liu, Stefan Kaiser, and Harald Giessen: Magnetoinductive and Electroinductive Coupling in Plasmonic Metamaterial Molecules, Advanced Materials 20, 4521 (2008).
[5] Na Liu, N. Liu, L. Langguth, T. Weiss, J. Kästel, M. Fleischhauer, T. Pfau, and H. Giessen: Plasmonic EIT analog at the Drude damping limit, Nature Materials 8, 758 (2009).
[6] Na Liu, T. Weiss, M. Mesch, L. Langguth, U. Eigenthaler, M. Hirschner, C. Sönnichsen, and H. Giessen: Planar metamaterial analog of electromagnetically induced transparency for plasmonic sensing, Nano Lett. 10, 1103 (2010).
[7] B. Lukyanchuk, N.I. Zheludev, S.A. Maier, N.J. Halas, P. Nordlander, H. Giessen, and C.T. Chong: The Fano resonance in plasmonic nanostructures and metamaterials, Nature Materials 9, 707 (2010).
[8] Na Liu, Hui Liu, Shining Zhu, and Harald Giessen: Stereometamaterials, Nature Photonics 3, 157 (2009).
[9] H. Liu, J. X. Cao, S. N. Zhu, N. Liu, R. Ameling, and Harald Giessen: Lagrange model for the chiral optical properties of plasmonic stereometamaterials, Phys. Rev. B 81, 241403(R) (2010).


Tuesday, November 23, 2010, 12:00. ICFO’s Auditorium