Catching Time-Reversed Microwave Coherent State Photons with 99.4% Absorption Efficiency
J. Wenner, Yi Yin, Yu Chen, R. Barends, B. Chiaro, Evan R. Jeffrey, J. Kelly, A. Megrant, Joshua Y. Mutus, C. Neill, P. J. J. O’Malley, P. Roushan, D. Sank, A. Vainsencher, T. C. White, Alexander N. Korotkov, Andrew N. Cleland, John M. Martinis · Physical Review Letters · 2014
We demonstrate a high-efficiency deterministic quantum receiver to convert flying qubits to stationary qubits. We employ a superconducting resonator, which is driven with a shaped pulse through an adjustable coupler. For the ideal ``time-reversed'' shape, we measure absorption and receiver fidelities at the single microwave photon level of, respectively, 99.41% and 97.4%. These fidelities are comparable with gates and measurement and exceed the deterministic quantum communication and computation fault-tolerant thresholds, enabling new designs of deterministic qubit interconnects and hybrid quantum computers.