Strong antibunching photons/photon pairs emission in two atoms cavity QED system with the Van der Waals interaction

Abstract

Weinvestigate the generation of antibunching photons and photon pairs in a two-atom cavity QED system leveraging interatomic van der Waals (vdW) interaction. We show that the vdW interaction shifts the two-atom excited state, enabling the suppression of two-photon excitation via destructive interference in a diamond configuration. This leads to antibunching photon emission with extremely high purity. Furthermore, by tuning the vdW interaction strength, the conditions for conventional and unconventional photon blockades can overlap, significantly enhancing single-photon emission. Conversely, at the antiblockade excitation frequency, quantum Monte Carlo simulations demonstrate the feasibility of generating antibunching photon pairs with a high purity and reasonable leaking rate by selecting appropriate driving field Rabi frequency and vdW interaction strength. These f indings on enhanced single/two-photon emission could lead to more efficient and brighter quantum light sources.