Research : Topological

In recent years, the search for topological insulators with quantum states peculiar to their surfaces and edges has become one of the most advanced physical physics and material sciences. The attempt to trace the topology of this electronic system to the system of photons is called topological photonics, and is rapidly developing. A feature of this technology is its high affinity for the optical vortex mode.

Optical vortex mode is capable of transmission with information on the spiral period of its wavefront (optical vortex multiplexing method OAM: Orbital angular momentum multiplexing), and is expected to be a future multiplexing technology. However, one of the charanges to this is that TE / TM is restricted in the operation mode in the optical circuit currently used in optical communications. Therefore, we are working on the invention of an optical circuit with a new function using an optical vortex by incorporating a topological photonics device as part of a conventional optical circuit.

List of reports

• Long-Hua Wu, Xiao Hu, “Scheme for Achieving a Topological Photonic Crystal by Using Dielectric Material”, Vol. 114, 22, 223901 (2015)
• Tomohiro Amemiya, Hibiki Kagami, Koichi Saito, Nobuhiko Nishiyama, Shigehisa Arai. “Topological Photonic Integrated Circuits for Controlling OAM light”, International Workshop Topology, Jun. 2019.
• Tomohiro Amemiya, Hibiki Kagami, Saito Koichi, Makoto Tanaka, Sho Okada, Nobuhiko Nishiyama, Xiao Hu, “Si-based orbital angular momentum demux using topological edge state waveguide”, The 80th JSAP Autumn Meeting 2019, Sep. 2019