He obtained a PhD from Department of Applied Physics, the University of Tokyo in 1988. He held positions at Institute of Solid State Physics, the University of Tokyo (1988-1993, research associate), at Department of Physics and Astronomy, University of Illinois at Urbana-Champaign (1991-1993, visiting scientist), and joined Hokkaido University subsequently. He spent a year in Germany (2000-2001) at University of Karlsruhe and at University of Bayreuth (half a year per each) as an overseas research fellow. He has been teaching quantum mechanics, thermodynamics, statistical mechanics, mathematical methods in physics, field theory in statistical mechanics, etc., over 20 years.