Entangling two levitated charged nanospheres through Coulomb interaction

Abstract Limited by the thermal environment, the entanglement of the massive object is extremely diffcult to be prepared. Based on the coherent scattering mechanism, we propose a scheme to generate the entanglement of two optically levitated nanospheres through the Coulomb interaction. Two nanospheres are charged and coupled with each other through the Coulomb interaction. In this manner, the entanglement of two nanospheres has been induced either under a weak/strong optomechanical coupling regime, or under an ultrastrong optomechanical coupling regime. The charges, radius, and distance of two nanospheres are taken into consideration to enhance the Coulomb interaction, thereby achieving a higher degree of the entanglement in the absence of the ground-state cooling. The corresponding maximum entanglement can be attained as the dynamics of the system approaches the boundary between the steady and the unsteady regime. It provides a useful resource for both quantum enhanced sensing and quantum information processing, as well as a new platform for studying the many-body physics.