Inflation in a modified radiative seesaw model

The existence of the inflationary era in the early Universe seems to be strongly supported by recent CMB observations. However, only a few realistic inflation scenarios which have close relation to particle physics seem to have been known unfortunately. The radiative neutrino mass model with inert doublet dark matter is a promising model for the present experimental issues which cannot be explained within the standard model. In order to make the model include inflation, we extend it by a complex scalar field with a specific potential. This scalar could be closely related to the neutrino mass generation at a TeV scale as well as inflation. We show that the inflation favored by the CMB observations could be realized even if inflaton takes sub-Planck values during inflation.