Exploring Unique Nanophotonic Phenomena by Electron Beam
To address ever-increasing volume of information and communications, there is an urgent need to develop photonics-electronics integrated devices for faster optical communications and information processing with less power loss. New developments in optical control using nanostructures are required because confining light to nanospace not only reduces the size of devices but also enhances the light-matter interaction, leading to the realization of high-speed, highly efficient devices.
Using electron energy loss spectroscopy (EELS), which is equivalent to absorption spectroscopy, and cathodoluminescence (CL), which analyzes the emission, we are searching for novel surface plasmon modes in nanostructures, and deepen understanding emitter-resonator coupled systems at the nanoscale.
Recent microfabrication techniques allow us to design and fabricate artificial crystals with periodic arrays of nanostructures, and to control plasmon propagation based on band theory. For example, properties derived from the geometry of crystal structures, such as topological insulators and valley polarization, are concepts that can be applied to various waves, including photons and plasmons. We aim to create new degrees of freedom to create new functional devices in combination with nanomaterial systems.
References
Cathodoluminescence Saturation Imaging to Visualize Emitter–Resonator Coupling
Hikaru Saito, Yuuichiro Kimura, Kentaro Matsuzaki, Yoshikazu Adachi, Sotatsu Yanagimoto, Kosuke Watanabe, Miki Inada, Takumi Sannomiya
ACS Nano 2025, 19, 21, 19590–19598
Light Emission Enhancement on Nanostructured Surfaces Quantitatively Evaluated by Cathodoluminescence Coincidence Counting
Tomoyasu Fujimaru, Hiromu Tanaka, Masato Inamata, Midori Ikeuchi, Hidehiro Yamashita, Hiroya Miyazaki, Takashi Gondo, Satoshi Hata, Mitsuhiro Murayama, Hikaru Saito
ACS Photonics 2025, 12, 6, 3073–3081
Valley-polarized plasmonic edge mode visualized in the near-infrared spectral range
Hikaru Saito, Daichi Yoshimoto, Yuto Moritake, Taeko Matsukata, Naoki Yamamoto, Takumi Sannomiya
Nano Lett. 2021, 21, 15, 6556–6562