A class of quintessential inflation models with parameter space   consistent with BICEP2
  In this paper, we focus on general features of quintessential inflation which is an effort to unify inflation and dark energy using a single scalar field. We describe a class of models of quintessential inflation which can give rise to the tensor to scalar ratio of perturbations consistent with recent BICEP2 measurements. The scale of inflation in the model is around the GUT scale and there is large parameter space consistent with the recent findings. 
Md. Wali Hossain, R. Myrzakulov, M. Sami, Emmanuel N. Saridakis
gr-qc astro-ph.CO hep-th