| Autor: |
Kandala A; IBM Quantum, IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA., Wei KX; IBM Quantum, IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA., Srinivasan S; IBM Quantum, IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA., Magesan E; IBM Quantum, IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA., Carnevale S; IBM Quantum, IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA., Keefe GA; IBM Quantum, IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA., Klaus D; IBM Quantum, IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA., Dial O; IBM Quantum, IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA., McKay DC; IBM Quantum, IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA. |
| Abstrakt: |
Improving two-qubit gate performance and suppressing cross talk are major, but often competing, challenges to achieving scalable quantum computation. In particular, increasing the coupling to realize faster gates has been intrinsically linked to enhanced cross talk due to unwanted two-qubit terms in the Hamiltonian. Here, we demonstrate a novel coupling architecture for transmon qubits that circumvents the standard relationship between desired and undesired interaction rates. Using two fixed frequency coupling elements to tune the dressed level spacings, we demonstrate an intrinsic suppression of the static ZZ while maintaining large effective coupling rates. Our architecture reveals no observable degradation of qubit coherence (T_{1},T_{2}>100 μs) and, over a factor of 6 improvement in the ratio of desired to undesired coupling. Using the cross-resonance interaction, we demonstrate a 180 ns single-pulse controlled not (cnot) gate, and measure a cnot fidelity of 99.77(2)% from interleaved randomized benchmarking. |
