Implementation of a quantum metamaterial using superconducting qubits

摘要: The key issue for the implementation of a metamaterial is to demonstrate existence collective modes corresponding coherent oscillations meta-atoms. Atoms natural materials interact with electromagnetic fields as quantum two-level systems. Artificial systems can be made, example, using superconducting nonlinear resonators cooled down their ground state. Here we perform an experiment in which 20 these meta-atoms, so-called flux qubits, are embedded into microwave resonator. We observe dispersive shift resonator frequency imposed by qubit and resonant coupling eight qubits. realized prototype represents mesoscopic limit naturally occurring spin ensembles such AC-Zeeman ensemble. studied system constitutes basic sense that many artificial atoms coupled collectively quantized mode photon field.