Dynamical Solution to Supersymmetric CP Problem with Vanishing B   Parameter
  The CP violation gives rise to severe restriction of soft breaking terms in supersymmetric standard models. Among them, constraints on the holomorphic soft mass of Higgs doublets (the B parameter) are difficult to satisfy due to the other inherent problem in the Higgs potential; the mu problem. In this letter, it is argued that these CP and mu problems can be rather relaxed provided that B is vanishing at high-energy scale. A generic mechanism and some examples of model are presented to dynamically realize this condition by introducing gauge singlet fields. 
Masahiro Yamaguchi and Koichi Yoshioka