Transitional CP violation in the MSSM and electroweak baryogenesis

Electroweak baryogenesis depends on the profile of the bubble wall created in the first-order phase transition. It is pointed out that CP violation in the Higgs sector of the MSSM could become large enough to explain the baryon asymmetry. We confirm this by solving the equations of motion for the Higgs fields with an effective potential at the transition temperature; that is, we present an example for which the transitional CP violation is realized and show the possibility that the baryon asymmetry of the universe may be produced, if marginally, by the tau lepton interacting with the wall when all explicit CP breaking in the Higgs sector is induced at the phase transition.