Preheating with nonminimally coupled scalar fields in higher-curvature inflation models

In higher-curvature inflation models (Formula presented) we study a parametric preheating of a scalar field (Formula presented) coupled nonminimally to a spacetime curvature (Formula presented) In the case of the (Formula presented)-inflation model, efficient preheating becomes possible for rather small values of (Formula presented) i.e., (Formula presented) several. Although the maximal fluctuation (Formula presented) for (Formula presented) is almost the same as the chaotic inflation model with a nonminimally coupled (Formula presented) field, the growth rate of the fluctuation becomes much larger and efficient preheating is realized. We also investigate preheating for the (Formula presented) model and find that the maximal fluctuation is (Formula presented) for (Formula presented)