Strain induced quantum Hall phenomena of excitons in graphene*

We predict quantum Hall phenomena for excitons such as the Integer and Fractional Quantum Hall effects, and the state of composite fermions at ν = 1/2 in a mono and double layer of gapped graphene under strain induced gauge pseudomagnetic field. When electrons and holes are excited only in one valley of the honeycomb lattice of gapped graphene, the strain induced pseudomagnetic field acts on electrons and holes the same way. The latter leads to the formation of single pseudomagnetoexcitons (PMEs) whose properties are cardinally different from those of magnetoexcitons. Wave functions and the energy spectrum of direct and indirect PMEs in a mono and double layer of gapped graphene are obtained. The valley Hall flows of direct and indirect PME’s, similar to Hall currents of charged particles, can be excited in a mono or double layer of gapped graphene, respectively. The predicted quantum Hall phenomena for the PMEs are important, since they imply that the quantum Hall physics and valleytronics phenomena can be observed in the novel system of neutral bosons without magnetic field.