Exploring pure spinor string theory on AdS4 x CP3

In this paper we formulate the pure spinor superstring theory on AdS(4) x CP3. By recasting the pure spinor action as a topological A-model on the fermionic supercoset Osp(6 vertical bar 4)/SO(6) x Sp(4) plus a BRST exact term, we prove the exactness of the sigma-model. We then give a gauged linear sigma-model which reduces to the superstring in the limit of large volume and we study its branch geometry in different phases. Moreover, we discuss possible D-brane boundary conditions and the principal chiral model for the fermionic supercoset.