Lawrence Berkeley National Laboratory

We investigate the possibility that the CP violation due to the soft supersymmetry breaking terms in squark mixing can give significant contributions to the various $\gamma$ related parameters in B decays, different from those of the Standard Model. We derive the new limits on $(\delta^u_12)_LL,LR,RR$ and on $(\delta^d_23)_LL,LR,RR$ from the recent data on $D^0$--$\barD^0$ oscillation as well as those on $B_s^0$--$\barB_s^0$ oscillation. We show that, together with all the other constraints, the currents limits on these parameters still allow large contributions to the CP violating phases in $B_s^0$--$\bar{B_s}^0$ as well as $D^0$--$\barD^0$ oscillations which will modify some of the proposed measurements of $\gamma$ parameters in CP violating B decays. However, the current constraints already dictate that the one-loop squark mixing contributions to various B decay amplitudes cannot be competitive with that of the Standard Model (SM), at least for those B decay modes which are dominated the tree level amplitudes within the SM, and therefore they are not significant in contributing to CP asymmetries in the corresponding B decays.