CP violation in charged Higgs boson decays
  CP violation in H^\pm decays into the three possible decay modes into ordinary particles, 1) H^\pm \to tb, 2) H^\pm \to \nu \tau and 3) H^\pm \to W^\pm h^0 is considered. Analytic expressions and numerical results for the CP violating decay rate asymmetries in the MSSM are obtained. Increasing \tan\beta the asymmetries for the fermionic decays, H^\pm \to tb and H^\pm \to \nu \tau, decrease and it increases for H^\pm \to W^\pm h^0. The asymmetry of H^\pm \to tb is most sensitive to the phase of $A_t and can go up to 20%, the asymmetries of 2) and 3) depend mainly on the phases of A_\tau and M_1. The asymmetry of 2) is smaller than 0.5% and of 3) can reach up to 2%. 
Ekaterina Christova, Helmut Eberl and Elena Ginina