Striped excitonic (super)solid in anisotropic semiconductors with screened exciton interactions

Within the Gross-Pitaevskii framework, we reveal the emergence of a crystallized phase of an exciton condensate in an atomically thin anisotropic semiconductor, where screening of exciton-exciton interactions is introduced by a proximal doped graphene layer. While such screened interactions are expected to yield a hexagonal crystal lattice in the excitonic condensate in isotropic semiconductor quantum wells [see, e.g., M. Matuszewski et al., Phys. Rev. Lett. 108, 060401 (2012)], here, we show that, for atomically thin semiconductors with strong electronic anisotropy, such as few-layer black phosphorus, the crystallized exciton phase acquires a parallel stripe structure. The optimal conditions for the emergence of this phase as well as its coexistence with excitonic superfluidity in a striped supersolid phase are identified.