Effects from the CP-violating Higgs sector in the two Higgs doublet model on the electroweak observable $R_b$ are analyzed. The $\mathrm{CP}$ violating one-loop corrections on $R_b$ are presented in terms of two categories of unknown parameters: the Higgs boson masses and their mixing angles. We investigate how much the one-loop radiative corrections $\delta R_b$ can be deviated from the $\mathrm{CP}$ conserving case for fixed Higgs boson masses when the mixing angles associated with $\mathrm{CP}$ violation are turned on. The dependence of $\delta R_b$ on the Higgs boson masses is also discussed.

• Received 7 August 2000

DOI:https://doi.org/10.1103/PhysRevD.63.056004