Subsequently, he joined Kyoto University and initiated research on photonic crystals. Next, he moved to Osaka University and was appointed the Research Director of the strategic basic research program CREST, “development of terahertz integrated technology platform through fusion of resonant tunneling diodes and photonic crystals” of the Japan Science and Technology Agency.,

His research interests include terahertz materials and devices, photonic nanostructures and microstructures, and their applications. He currently serves as an Associate Editor for Applied Physics Express, and a chair of the Technical Group on Terahertz Application Systems of Information and Communication Engineers (IEICE), Japan.