Recently , BICEP2 has reported the large tensor-to-scalar ratio r = 0.2 ^ { +0.07 } _ { -0.05 } from the observation of the cosmic microwave background ( CMB ) B-mode at degree-scales .
Since tensor modes induce not only CMB B-mode but also the temperature fluctuations on large scales , to realize the consistent temperature fluctuations with the Planck result we should consider suppression of scalar perturbations on corresponding large scales .
To realize such a suppression , we consider anti-correlated iso-curvature perturbations which could be realized in the simple curvaton model .