Temperature dependent Electron Land\'e g-Factor and Interband Matrix   Element in GaAs
  Very high precision measurements of the electron Lande g-factor in GaAs are presented using spin-quantum beat spectroscopy at low excitation densities and temperatures ranging from 2.6 to 300 K. In colligation with available data for the temperature dependent effective mass a temperature dependence of the interband matrix element within a common five level kp-theory can model both parameters consistently. A strong decrease of the interband matrix element with increasing temperature consistently closes a long lasting gap between experiment and theory and substantially improves the modeling of both parameters. 
J. H\"ubner, S. D\"ohrmann, D. H\"agele, and M. Oestreich