Photon-mediated interactions between distant artificial atoms

Understand

Photon-mediated interactions between atoms are of fundamental importance in quantum optics, quantum simulations and quantum information processing.

• The exchange of real and virtual photons between atoms gives rise to non-trivial interactions the strength of which decreases rapidly with distance in three dimensions.
• Here we study much stronger photon mediated interactions using two superconducting qubits in an open onedimensional transmission line.
• Making use of the unique possibility to tune these qubits by more than a quarter of their transition frequency we observe both coherent exchange interactions at an effective separation of $3\lambda/4$ and the creation of super- and sub-radiant states at a separation of one photon wavelength $\lambda$.