Dipole-coupled emitters as deterministic entangled photon-pair sources

Abstract

Scalable quantum systems require deterministic entangled photon pair sources. Here, we demonstrate a scheme that uses a dipole-coupled emitter pair to deterministically emit polarization-entangled photon pairs. Based on this scheme, we predict spectroscopic signatures and quantify the entanglement with realistic material parameters. In addition, we describe how the Bell state fidelity and efficiency can be optimized by precisely tuning transition frequencies. Finally, we discuss how defect emitters are natural candidates for the proposed scheme, offering numerous advantages including flexible on-chip photonic integration and tunable emission properties via external fields, electromagnetic environments, and defect selection.