RIKEN Center for Emergent Matter Science Emergent Photodynamics Research Group

Group Director: Naoki Ogawa (Ph.D.)

Japanese Page

Research Summary

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

Keywords

Optical properties of condensed matter

Selected Publications

1. Wang, Z., Wang, M., Lehmann, J., Shiomi, Y., Arima, T., Nagaosa, N., Tokura, Y., and Ogawa, N.,
"Electric-field-enhanced second-harmonic domain contrast and nonreciprocity in a van der Waals antiferromagnet"
Nature Commun. 15, 7542 (2024)
2. 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)
3. 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)
4. 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)
5. 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)
6. 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)
7. Toyoda, S., Fiebig, M., Arima, T., Tokura, Y., and Ogawa, N.,
"Nonreciprocal second harmonic generation in a magnetoelectric material"
Sci. Adv. 7, eabe2793 (2021)
8. Ogawa, N. Köhler, 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)
9. 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)
10. 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)

Recent Research Results

Feb. 14, 2025
Shining a light on magnetic structure
Sep. 25, 2015
A magnetic memory bubbling with opportunity

Lab Members

Principal investigator

Naoki Ogawa: Group Director

Core members

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

Contact Information

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