Research Themes
At the National Institute for Materials Science (NIMS), we conduct research on the physics and applications of photonic devices, including metal nanophotonics (“plasmonics”) and artificial optical media (“metamaterials”). We aim to create innovative photonic devices utilizing nanostructures combining negative-index dielectrics (metals) and high-refractive-index dielectrics. Recently, we have been focusing particularly on research into "metasurfaces," which are two-dimensional metamaterials, and are advancing research on dielectric metasurfaces using silicon. In fundamental research, we are studying the optical response of systems combining two-dimensional nanomaterials—including graphene and transition metal dichalcogenides—with Meissner resonators, focusing on ultra-thin perfect absorbers achieved through degenerate critical coupling using multipoles within silicon Mie resonators.
In applied research, we have collaborated with companies to realize high-resolution color generation, optical switches utilizing massive nonlinear optical scattering up to 100,000 times greater than bulk materials, and radiative cooling devices.
Our laboratory operates the Photonics Center, providing an environment for fostering innovation through the use of the center's shared equipment and interaction among members from different fields.
■ Metamaterial & Metasurface
Metamaterial is an artificial optical medium composed of numerous nanostructured resonators (meta-atoms). A two-dimensional metamaterial is called a metasurface. Recently, we have focused our research on lossless dielectric metasurfaces that do not use metals. We fabricate metamaterials using silicon as a high-refractive-index dielectric. Our research focuses on structural colors, perfect absorbers, and selective radiation emitters using silicon metasurfaces, along with their applications.Keywords: metamaterials, metasurface, active metamaterial, hyperbolic metamaterial, all dielectric metasurface, Mie resonator, Magnetic Dipole, Huygens metasurface, degenerate critical coupling, troidal dipole）, Non-Hermetioan photonic
■ Plasmonics
We are conducting research on the physics of surface plasmon polariton, which is low-dimensional optical waves existing at the interface between metal (negative dielectrics) and dielectrics, and their applications in optical devices. Utilizing surface plasmon polariton enables the transmission of nanometer-scale light beams beyond the diffraction limit of light, making them promising for application in nano-optical integrated circuits. This field, now called plasmonics, is currently the subject of active research and development worldwide.Keywords: Nanophotonics, plasmonics, plasmonic waveguide, active plasmonics, optical antenna, plasmonic color, low-dimensional optical waves, refractory plasmonics
■ Thermal Radiation Control
From the perspective of high-temperature plasmonics, we are conducting research on thermal radiation control using micro/nanostructures. By artificially forming microcavity array structures on the surface of materials, it is possible to control the thermal radiation spectrum and polarization independently of the material itself. This can be described as applying the concept of thermal radiation control through structures, not materials. This is expected to be applied to narrow-band thermal radiation light sources or high-efficiency incandescent bulbs. In recent years, energy-saving and environmentally friendly photonics, known as green photonics, has been attracting attention, and research on thermal radiation control is also attracting attention from the perspective of green photonics.Keywords: thermal plasmonics, refractory plasmonics, Thermal radiation control by microstructures , 完全吸収体, microcavity, spoof-surface plasmon, incandescent lamps, IR emitter, radiative cooling, sky radiator