Centers & Labs

RIKEN Center for Emergent Matter Science

Emergent Photodynamics Research Team

Team Leader: Naoki Ogawa (Ph.D.)
Naoki  Ogawa(Ph.D.)

Our research unit explores novel photodynamics of electron/spin in bulk crystals and at thin-film interfaces emerging via electron-correlation and strong spin-orbit interactions. Examples are the spin current generation mediated by photoexcited Dirac electrons and the ultrafast coherent control/spectroscopy of topological spin textures. With a strong command of photons, we try to realize new photomagnetic effects in solids, and visualize the spatiotemporal propagation of elementally excitations at the sub-diffraction limit.

Main Research Field

Mathematical and physical sciences

Related Research Fields



  • Optical spectroscopy

Selected Publications

  1. Bahramy, M. S. and Ogawa, N.
    "Bulk Rashba Semiconductor and Related Quantum Phenomena"
    Adv. Mater. 1605911 (2017).
  2. Sheu, Y. M., Ogawa, N., Kaneko, Y., and Tokura, Y.
    "Photocreating supercooled spiral-spin states in a multiferroic manganite"
    Phys. Rev. B 94, 081107(R) (2016).
  3. 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).
  4. Okada, K. N., Takahashi, Y., Yoshimi, R., Tsukazaki, A., Takahashi, K. S., Ogawa, N., Kawasaki, M., and Tokura, Y.
    "Terahertz spectroscopy on Faraday and Kerr rotations in a quantum anomalous Hall state"
    Nature Commun. 7, 12245 (2016).
  5. 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, 8977-8981 (2015).
  6. Ogawa, N., Seki, S., and Tokura, Y.
    "Ultrafast optical excitation of magnetic skyrmions"
    Sci. Rep. 5, 9552 (2015).
  7. Ogawa, N., Bahramy, M. S., Kaneko, Y., Tokura, Y.
    "Photocontrol of Dirac electrons in a Rashba semiconductor"
    Phys. Rev. B 90, 125122 (2014).
  8. Ogawa, N., Bahramy, M. S., Murakawa, H., Kaneko, Y., and Tokura, Y.
    "Magnetophotocurrent in BiTeI with Rashba spin-split bands"
    Phys. Rev. B 88, 035130 (2013).
  9. Ogawa, N., Ogimoto, Y., Ida, Y., Nomura, Y., Arita, R., and Miyano, K.
    "Polar antiferromagnets produced with orbital-order"
    Phys. Rev. Lett. 108, 157603 (2012).
  10. Wu, S. W., Ogawa, N., and Ho, W.
    "Atomic-Scale Coupling of Photons to Single-Molecule Junctions"
    Science 312, 1362-1365 (2006).

Lab Members

Principal Investigator

Naoki Ogawa
Team Leader

Core Members

Masato Sotome
Postdoctoral Researcher
Shingo Toyoda
Postdoctoral Researcher

Contact information

Frontier Research Laboratory,
2-1 Hirosawa,
Wako, Saitama
351-0198, Japan

Email: naoki.ogawa [at]