  We perform the first investigation of cold electroweak baryogenesis in the
two Higgs-doublet model (2HDM). The electroweak symmetry breaking transition is
assumed to occur through a spinodal instability from a super-cooled initial
state. We consider the creation of net Chern-Simons number, which through the
axial anomaly is equivalent to baryon number. CP-violation is explicit in the
scalar potential, but only in combination with P-violation is it possible for
an asymmetry to be generated. This is introduced through the leading C- and
P-breaking, but CP-invariant, term expected to arise upon integrating out the
fermions in the theory. We perform real-time lattice simulations of the
transition, and find the coefficient of this term required for successful
bayogenesis.
