Centers & Labs

RIKEN Center for Emergent Matter Science

Emergent Spectroscopy Research Unit

Unit Leader: Youtarou Takahashi (Ph.D.)
Youtarou  Takahashi(Ph.D.)

Optical phenomena are critical for understanding the physical properties of matter, while the material with a particular property provides the novel optical phenomena. Our current research interests focus on the novel optical phenomena driven by the strong coupling between the dielectric and magnetic properties in matter, the optical control of the state of matter and the conduction electron dynamics in the strongly correlated electron system. The dynamical responses of the strongly correlated systems are investigated by the state-of-the-art laser spectroscopy including the terahertz and ultrafast spectroscopy.

Main Research Field


Related Research Fields


Research Subjects

  • Novel magnetoelectric optics on electromagnons
  • Ultrafast spin dynamics in multiferroics
  • Terahertz spectroscopy on strongly correlated electron system

Selected Publications

  1. Takahashi, Y., Chakraverty, S., Kawasaki, M., Hwang, H. Y., and Tokura, Y.:
    "In-plane terahertz response of thin film Sr2RuO4"
    Phys. Rev. B89, 165116 (2014).
  2. Ueda, K., Fujioka, J., Takahashi, Y., Suzuki, T., Ishiwata, S., Taguchi, Y., Kawasaki, M. and Tokura, Y.:
    "Anomalous domain-wall conductance in Pyrochlore-type Nd2Ir2O7 on the verge of metal-insulator transition"
    Phys. Rev. B89, 075127 (2014).
  3. Takahashi, Y., Yamasaki, Y., and Tokura, Y.:
    "Terahertz Magnetoelectric Resonance Enhanced by Mutual Coupling of Electromagnons"
    Phys. Rev. Lett.111.037204 (2013).
  4. Ueda, K., Fujioka, J., Takahashi, Y., Suzuki, T., Ishiwata, S., Taguchi, Y., and Tokura, Y.:
    "Variation of Charge Dynamics in the Course of Metal-Insulator Transition for Pyrochlore-Type Nd2Ir2O7"
    Phys. Rev. Lett.109.136402 (2012).
  5. Takahashi, Y., Shimano, R., Kaneko, Y., Murakawa, H., and Tokura, Y.:
    "Magnetoelectric resonance with electromagnon in a perovskite helimagnet"
    Nature Physics 8, 121-125 (2012).

Contact information

Quantum-Phase Electronics Center,
School of Engineering,
The University of Tokyo,
7-3-1 Hongo, Bunkyo-ku,
113-8656, Japan

Email: youtarou.takahashi [at]