Topological nature of nonlinear optical effects in solids

There are a variety of nonlinear optical effects including higher harmonic generations, photovoltaic effects, and nonlinear Kerr rotations. They are realized by strong light irradiation to materials that results in nonlinear polarizations in the electric field. These are of great importance in studying the physics of excited states of the system as well as for applications to optical devices and solar cells. Nonlinear properties of materials are usually described by nonlinear susceptibilities, which have complex expressions including many matrix elements and energy denominators. On the other hand, a nonequilibrium steady state under an electric field periodic in time has a concise description in terms of the…

• GA
  Gordon and Betty Moore Foundation

  Award: ID0E43AE6604
• MO
  Ministry of Education, Culture, Sports, Science and Technology

  Awards: JSPS Grant-in-Aid for Scientific Research (No. 24224009, and No. 26103006), ID0E1YAE6603