Canonical transformation approach to the ultrafast nonlinear optical dynamics of semiconductors

Academic Article

Abstract

  • We develop a theory describing the effects of many-particle Coulomb correlations on the coherent ultrafast nonlinear optical response of semiconductors and metals. Our approach is based on a mapping of the nonlinear optical response of the "bare" system onto the linear response of a "dressed" system. The latter is characterized by effective time-dependent optical transition matrix elements, electron/hole dispersions, and interaction potentials, which in undoped semiconductors are determined by the single-exciton and two-exciton Green functions in the absence of optical fields. This mapping is achieved by eliminating the optically-induced charge fluctuations from the Hamiltonian using a Van Vleck canonical transformation. It takes into account all many-body contributions up to a given order in the optical fields as well as important Coulomb-induced quantum dynamics to all orders in the optical field. Our approach allows us to distinguish between optical nonlinearities of different origins and provides a physically-intuitive interpretation of their manifestations in ultrafast coherent nonlinear optical spectroscopy. © World Scientific Publishing Company.
  • Authors

    Digital Object Identifier (doi)

    Author List

  • Perakis IE; Shahbazyan TV
  • Start Page

  • 869
  • End Page

  • 893
  • Volume

  • 13
  • Issue

  • 8