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RIKEN Center for Emergent Matter Science Emergent Photodynamics Research Group

Group Director: Naoki Ogawa (Ph.D.)

Research Summary

Naoki  Ogawa(Ph.D.)

Our team explores novel photodynamics of electron/spin/lattice in bulk crystals and at thin-film interfaces emerging via electron-correlation, strong spin-orbit interaction, and topology. Examples are ultrafast spectroscopy on shift/injection current, generation of spin current mediated by Dirac/Weyl electrons, and manipulation of topological magnetic textures. With a strong command of photons, we try to realize new photo-electric/magnetic effects in solids, and visualize spatiotemporal propagation of various elemental excitations at the sub-diffraction limit.

Main Research Fields

  • Mathematical & Physical Sciences

Related Research Fields

  • Condensed matter physics


  • Optical properties of condensed matter

Selected Publications

  • 1. Wang, Z., Zhang, X.-X., Shiomi, Y., Arima, T., Nagaosa, N., Tokura, Y., and Ogawa, N.:
    "Exciton-magnon splitting in van der Waals antiferromagnet MnPS3 unveiled by second-harmonic generation"
    Phys. Rev. Res. 5, L042032 (2023)
  • 2. Toyoda, S., Liao, J.-C., Guo, G.-Y., Tokunaga, Y., Arima, T., Tokura, Y., and Ogawa, N.:
    "Magnetic-field switching of second harmonic generation in noncentrosymmetric magnet Eu2MnSi2O7"
    Phys. Rev. Mater. 7, 024403 (2023)
  • 3. Wang, Z., Gao, M., Yu, T., Zhou, S., Xu, M., Hirayama, M., Arita, R., Shiomi, Y., Zhou, W., and Ogawa, N.:
    "Real-Space Observation of Ripple-Induced Symmetry Crossover in Ultrathin MnPS3"
    ACS Nano 17, 1916-1924 (2023)
  • 4. Toyoda, S., Yamada, R., Kaneko, Y., Tokura, Y., and Ogawa, N.:
    "Weyl fermions in SrRuO3 detected by Brillouin light scattering"
    Appl. Phys. Lett. 120, 242408 (2022)
  • 5. Toyoda, S., Fiebig, M., Forster, L., Arima, T., Tokura, Y., and Ogawa, N.:
    "Writing of strain-controlled multiferroic ribbons into MnWO4
    Nature Commun. 12, 6199 (2021).
  • 6. Toyoda, S., Fiebig, M., Arima, T., Tokura, Y., and Ogawa, N.:
    "Nonreciprocal second harmonic generation in a magnetoelectric material"
    Sci. Adv. 7, eabe2793 (2021)
  • 7. Ogawa, N. Kohler, L., Garst, M., Toyoda, S., Seki, S., and Tokura, Y.:
    "Nonreciprocity of spin-waves in the conical helix state"
    Proc. Natl. Acad. Sci. 118, e2022927118 (2021)
  • 8. Sotome, M., Nakamura, M., Fujioka, J., Ogino, M., Kaneko, Y., Morimoto, T., Zhang, Y., Kawasaki, M., Nagaosa, N., Tokura, Y., and Ogawa, N.:
    "Spectral dynamics of shift-current in ferroelectric semiconductor SbSI"
    Proc. Natl. Acad. Sci. 116, 1929 (2019)
  • 9. Ogawa, N., Yoshimi, R., Yasuda, K., Tsukazaki, A., Kawasaki, M., and Tokura, Y.:
    "Zero-bias photocurrent in ferromagnetic topological insulator"
    Nature Commun. 7, 12246 (2016)
  • 10. Ogawa, N., Koshibae, W., Beekman, A. J., Nagaosa, N., Kubota, M., Kawasaki, M., and Tokura, Y.:
    "Photo-drive of magnetic bubbles via magnetoelastic waves"
    Proc. Natl. Acad. Sci. 112, 8977 (2015)

Recent Research Results

Related Links

Lab Members

Principal investigator

Naoki Ogawa
Group Director

Core members

Shingo Toyoda
Research Scientist
Manfred Fiebig
Senior Visiting Scientist
Tsubasa Takagi
Junior Research Associate
Lucille Ascenci


Position Deadline
Seeking a Postdoctoral Researcher (W23335) Open until filled

Contact Information

Frontier Research Laboratory,
2-1 Hirosawa,
Wako, Saitama
351-0198, Japan
Email: naoki.ogawa [at] riken.jp