Metamaterials Laboratory

In the past, it has been believed that the electro-magnetic properties of materials are determined by the intrinsic property of the materials itself and no one can alter them. This suggests that the propagation of the light inside the material is uniquely determined by the material itself and it can only be controlled by modifying the shapes/structures of the materials. In this research laboratory, we are intensively investigating the breakthrough science and techniques that can artificially control the electro-magnetic properties of the materials by using metal nano-structures. This technology can create unprecedented optical materials such that it can interact directly with the magnetic components of the light, in which the refractive index can be zero, negative or tremendously giant values. We collectively call these kinds of artificial materials - "metamaterials". We will also extend the application of metamaterials to develop novel and functional optical devices that will open a door for new photonic technologies.

Research Subjects

• Creation of plasmonic metamaterials that work at visible light frequency region.
• Application of plasmonic metamaterial technology to the optical functional devices.
• Development of three-dimensional nano-scale metal fabrication techniques for 3D metamaterials.
• Development of three-dimensional high-capacity optical storege technology

Publications

1. Ryoko Watanabe-Tamaki, Atsushi Ishikawa, Takuo Tanaka, Tamotsu Zako, and Mizuo Maeda:
   "DNA-Templating Mass Production of Gold Trimer Rings for Optical Metamaterials"
   The Journal of Physical Chemistry C 116, pp. 15028-15033 (2012)
2. Kanna Aoki, Kentaro Furusawa, and TakuoTanaka:
   "Magnetic assembly of gold core-shell necklace resonators"
   Applied Physics Letters 100, 181106 (2012)
3. Atsushi Ishikawa and Takuo Tanaka:
   "Two-Photon Fabrication of Three-Dimensional Metallic Nanostructures for Plasmonic Metamaterials"
   J. Laser Micro/Nanoeng. 7, 1, pp. 11-15 (2012)
4. Takuo Tanaka:
   "Two-photon Recording and Plasmon-Enhanced Read-Out of Three-Dimentional Optical Disk with Ten Recording Layers"
   Jpn. J. Appl. Phys. 50, 9, pp.902 (2011)
5. T. Ohshiro, T. Zako, R. W.-Tamaki, T. Tanaka and M. Maeda:
   "A facile method towards cyclic assembly of gold nanoparticles using DNA template alone"
   Chem. Commun. 46, pp. 6132 (2010)
6. Yao-Yu Cao, Nobuyuki Takeyasu, Takuo Tanaka, Xuan-Ming Duan, and Satoshi Kawata:
   "3D Metallic Nano-Structure Fabrication By Surfactant-Assisted Multi-Photon-Induced Reduction"
   Small 5, pp. 1144-1148 (2009)
7. A. Ishikawa, T. Tanaka, and S. Kawata:
   "Magnetic Excitation of Magnetic Resonance in Metamaterials at Far-Infrared Frequencies"
   Appl. Phys. Lett. 91, 113118 (2007)
8. T. Tanaka, A. Ishikawa, and S. Kawata:
   "Unattenuated light transmission through the interface between two materials with different indices of refraction using magnetic metamaterials"
   Phys. Rev. B 73, 125423 (2006)
9. T. Tanaka, A. Ishikawa, and S. Kawata:
   "Two-photon-induced reduction of metal ions for fabricating three-dimensional electrically conductive metallic microstructure"
   Appl. Phys. Lett. 88, 81107 (2006)
10. A. Ishikawa, T. Tanaka, and S. Kawata:
    "Negative Magnetic Permeability in the Visible Light Region"
    Phys. Rev. Lett. 95, 237401 (2005)