Faculty

Junko Omachi

Major research activity

JunkoOmachiShe received her PhD degree at the University of Tokyo in 2010. For her doctoral work, she has investigated how photo-excited carriers behave in highly degenerate systems with many-body interactions at low temperatures on diamond under ultraviolet light irradiation by the pump-probe spectroscopy and time-resolved luminescence spectroscopy. After that, she has worked for light source development including sub-10-fs Ti: Sapphire mode-locked laser, cavity-enhanced second harmonic generation, and also was involved in the study of ultrafast photo-induced dynamics on molecules with two-dimensional electron spectroscopy. She also has worked on ultra-broadband rapid-scan Fourier-transform coherent Raman spectroscopy, which has a great promise for tracking fast kinetics in chemical phenomena. For her contributions to the light source development for the photoemission spectroscopy, she has received Young Scientist Presentation Award from the Japan Society of Applied Physics. She is interested in how to track the initial process of single-shot phenomena, such as aggregation process of biomolecules, by harnessing laser light source.

Major relevant publications

  1. Nenov A, Borrego-Varillas R, Oriana A, Ganzer L, Segatta F, Conti I, Segarra-Marti J, Omachi J, Dapor M, Taioli S, Manzoni C, Mukamel S, Cerullo G, Garavelli M: UV-light induced vibrational coherences, the key to understand Kasha rule violation in trans-azobenzene, J. Phys. Chem. Lett. 9, 7, 1534-1541 (2018).
  2. Xing Fan, Shusei Kamioka, Toshiaki Inada, Takayuki Yamazaki, Toshio Namba, Shoji Asai, Junko Omachi, Kosuke Yoshioka, Makoto Kuwata-Gonokami, Akira Matsuo, Koushi Kawaguchi, Koichi Kindo, Hiroyuki Nojiri:”The OVAL experiment: A new experiment to measure vacuum magnetic birefringence using high repetition pulsed magnets,” Eur. Phys. J. D 71: 308-1-10 (2017).
  3. Y. Suzuki, T. Shimojima, T. Sonobe, A. Nakamura, M. Sakano, H. Tsuji, J. Omachi, K. Yoshioka, M. Kuwata-Gonokami, T. Watashige, R. Kobayashi, S. Kasahara, T. Shibauchi, Y. Matsuda, Y. Yamakawa, H. Kontani, and K. Ishizaka: Momentum-dependent sign-inversion of orbital polarization in superconducting FeSe, Phys. Rev. B 92, 205117 (2015).
  4. J. Omachi, T. Suzuki, K. Kato, N. Naka, K. Yoshioka, and M. Kuwata-Gonokami: Observation of excitonic N-body bound states: polyexcitons in diamond, Phys. Rev. Lett., 111 026402-1-5 (2013).
  5. Nobuko Naka and Junko Omachi: Trailing quantum phases in solids using light-matter interaction, Chapter 17 in “New Developments in Photon and Material Research” (NOVA Science Publishers, 2013) p.365-382.
  6. J. Omachi, K. Yoshioka, and M. Kuwata-Gonokami: High-power, narrow-band, high-repetition-rate, 5.9 eV coherent light source using passive optical cavity for laser-based angle-resolved photoelectron spectroscopy, Opt. Exp. 20, 23542-23552 (2012).