Researchers have theoretically demonstrated the generation of quantum entanglement between electromagnetic field modes in two cavities separated by a movable conducting wall. Unlike a system with a fixed wall, where no entanglement is observed, the quantum interaction of the movable wall with the fields induces a quantum correlation between the field modes of the sub-cavities. This finding opens new avenues for the manipulation and study of entangled quantum states in optomechanical systems.

The system under study consists of a finite-mass, quantum mechanically treated conducting wall, subject to position fluctuations, placed between two fixed walls. This configuration creates two sub-cavities, each containing a massless one-dimensional scalar field. The effective interaction between the movable wall and the fields, as well as between the field modes themselves, is described by a generalization of the Law Hamiltonian. Entanglement was calculated analytically using negativity, a measure of entanglement, and confirmed numerically for the multimode case.

The results, obtained through second-order perturbation theory, reveal that the fields in the two sub-cavities are entangled. The amount of entanglement depends on key physical parameters such as the mass and oscillation frequency of the movable wall, its distance from the fixed walls, and the frequencies of the field modes considered. This work provides a theoretical framework for exploring entanglement generation in optomechanical systems, which could have implications for the development of new quantum technologies and the understanding of quantum interactions at macroscopic scales.