Quantum entanglement between two excitons in graphene under strain*

It has been shown that the Hamiltonian for excitons in graphene under strain is similar to that for the charge carriers in a magnetic field, which is not coupled to the charges. In this environment electrons and holes can form bound states in discrete Landau levels called Pseudomagnetoexcitons (PMEs). Provided that localization of charge carriers at the impurities on the graphene sheet removes degeneracy of Landau levels, PMEs can be treated as qubits. We assume the interaction between two such PMEs that are coupled to a single cavity mode. We have investigated the quantum entanglement of the pair of excitons by analyzing the concurrence in the system for several cases. We also considered an imperfect cavity, with leaking photons and numerically calculated how the concurrence evolves in time. For the system without dissipation, we applied a Jaynes-Cummings-like model for the interaction between two qubits in a single cavity mode. This was solved exactly for the resonant case, where the photonic energy is equal to the qubit energy gap. In the presence of dissipation, we numerically solved the Lindblad Master equation that governs the evolution.