Non-minimal coupling in inflation and inflating with the Higgs boson
  We analyse the effect of the non-minimal coupling of the form $\xi\phi^2R/2$ on the single field inflation. If the non-minimal coupling is large, it relaxes the constraint on the field self coupling, making it possible to use the Standard Model Higgs field as the inflaton. At the same time, even small non-minimal coupling constant, $\xi\gtrsim10^{-3}$, brings the usual inflaton with quartic potential in agreement with the WMAP5 observations. 
F.L. Bezrukov