Centers & Labs

Chief Scientist Laboratories

Condensed Matter Theory Laboratory

Chief Scientist: Akira Furusaki (D.Sci.)
Akira  Furusaki(D.Sci.)

We aim to understand theoretically various properties of materials of macroscopic scale from the physical laws that govern microscopic world. Many-electron systems having infinite degrees of freedom exhibit rich physical phenomena: they can have phases with spontaneously broken symmetry and transitions among these phases. A typical example is offered by magnetism and superconductivity in strongly-correlated electron systems, such as transition metal oxides and molecular conductors, which are the main research subjects of our laboratory. Our recent research subjects include unconventional ordered states and spin liquids in strongly frustrated quantum magnets and other new kinds of quantum phases like topological insulators and topological superconductors. Furthermore, we study quantum phenomena in mesoscopic systems of nanometer scale and statistical physics of random systems.

Main Research Field


Related Research Fields

Materials Sciences

Research Subjects

  • Quantum many-body systems
  • Quantum critical phenomena
  • Disordered quantum systems

Selected Publications

  1. Morimoto, T., Ueda, H., Momoi, T., and Furusaki, A.:
    "Z3 symmetry-protected topological phases in the SU(3) AKLT model"
    Phys. Rev. B 90, 235111 (2014).
  2. Matveev, K.A. and Furusaki, A.:
    "Decay of fermionic quasiparticles in one-dimensional quantum liquids"
    Phys. Rev. Lett. 111, 256401 (2013).
  3. Seo, H., Ishibashi, S., Otsuka, Y., Fukuyama, H., and Terakura, K.:
    "Electronic states of single-component molecular conductors [M(tmdt)2]"
    J. Phys. Soc. Jpn. 82, 054711 (2013).
  4. Furukawa, S., Sato, M., Onoda, S., and Furusaki, A.:
    "Ground-state phase diagram of a spin-1/2 frustrated ferromagnetic XXZ chain: Haldane dimer phase and gapped/gapless chiral phases"
    Phys. Rev. B 86, 094417 (2012).
  5. Momoi, T., Sindzingre, and Kubo, K.:
    "Spin nematic order in multiple-spin exchange models on the triangular lattice"
    Phys. Rev. Lett. 108, 057206 (2012).
  6. Tanaka, Y., Furusaki, A., and Matveev, K.A.:
    "Conductance of a helical edge liquid coupled to a magnetic impurity"
    Phys. Rev. Lett. 106, 236402 (2011).
  7. Onoda, S. and Tanaka, Y.:
    "Quantum melting of spin ice: emergent cooperative quadrupole and chirality"
    Phys. Rev. Lett. 105, 047201 (2010).
  8. Ryu, S., Schnyder, A.P., Furusaki, A., and Ludwig, A.W.W.:
    "Topological insulators and superconductors: tenfold way and dimensional hierarchy"
    New J. Phys. 12, 065010 (2010).
  9. Schnyder, A.P., Ryu, S., Furusaki, A., and Ludwig, A.W.W.:
    "Classification of topological insulators and superconductors in three spatial dimensions"
    Phys. Rev. B 78, 195125 (2008).
  10. Hikihara, T., Kecke, L., Momoi, T., and Furusaki, A.:
    "Vector chiral and multipolar orders in the spin-1/2 frustrated ferromagnetic chain in magnetic field"
    Phys. Rev. B 78, 144404 (2008).

Lab Members

Principal Investigator

Akira Furusaki
Chief Scientist

Core Members

Tsutomu Momoi
Senior Research Scientist
Shigeki Onoda
Senior Research Scientist
Hitoshi Seo
Senior Research Scientist
Sho Nakosai
Special Postdoctoral Researcher
Ryuji Takahashi
Special Postdoctoral Researcher
Yoshitomo Kamiya
Special Postdoctoral Researcher
Xavier Plat
Postdoctoral Researcher
Shunsuke Furuya
Visiting Researcher

Contact information

2-1 Hirosawa, Wako, Saitama 351-0198, Japan

Email: furusaki [at]

Related links

Recent research results

November 20, 2015: RIKEN RESEARCH
Melting of frozen frustrations

Annual research report