Quantum corrections to the spin-independent cross section in the inert Higgs doublet model

The inert Higgs doublet model is an extension of the standard model with an extra scalar doublet. The extra doublet is $Z_2$ odd while all the other particles are $Z_2$ even, thus the model contains a dark matter candidate. It is known that the spin-independent cross section of the dark matter and the nucleon is highly suppressed for $m_{\text DM} \sim m_h/2$ at the tree level. In this talk, we show the loop corrections give the significant effects in this regime.