Metasurface-Mediated Quantum Entanglement

Entanglement-based quantum science exploits subtle properties of quantum mechanics into applications such as quantum computing, sensing, and metrology. The emerging route for quantum computing applications, which calls for ultracompact, integrated, and scalable architecture, aims at onchip entangled qubits. In this context, quantum entanglement among atomic qubits was achieved via cold-controlled collisions which are only significant at subwavelength separations. However, as other manifolds of quantum state engineering require single-site addressability and controlled manipulation of the individual qubit using diffraction-limited optics, entanglement of qubits separated by macroscopic distances at the chip level is still an outstanding challenge. Here, we report a novel platform for on-chip quantum state engineering by harnessing the extraordinary light-molding capabilities of metasurfaces. We theoretically demonstrate quantum entanglement between two qubits trapped on a chip and separated by macroscopic distances, by engineering their coherent and dissipative interactions via the metasurface. Spatially scalable interaction channels offered by the metasurface enable robust generation of entanglement, with large values of concurrence and remarkable revival from sudden death. The metasurface route to quantum state engineering opens a new paradigm for on-chip quantum science and technologies.