Electroweak baryogenesis and quantum corrections to the triple Higgs boson coupling

A phenomenological consequence of electroweak baryogenesis is studied in connection with the Higgs physics. In a two Higgs doublet model, the first-order phase transition can be strong enough to allow the electroweak baryogenesis due to the effect of extra Higgs bosons. We investigate the quantum correction to the triple coupling of the lightest Higgs boson in such a scenario, and find that the condition of the strong first-order phase transition necessarily leads to the deviation of at least 10% from the Standard Model prediction. Such magnitude of the deviation can be identified in future e(+)e(-) linear collider experiments. We also discuss the minimal supersymrnetric standard model with the light stop scenario, and point out that a sizable correction appears in the triple coupling for successful electroweak baryogenesis. (C) 2004 Elsevier B.V. All rights reserved.