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arXiv · 1907.02510

Diabatic gates for frequency-tunable superconducting qubits

R. Barends·C. M. Quintana·A. G. Petukhov·Yu Chen·D. Kafri·K. Kechedzhi·R. Collins·O. Naaman·S. Boixo·F. Arute·K. Arya·D. Buell·B. Burkett·Z. Chen·B. Chiaro·A. Dunsworth·B. Foxen·A. Fowler·C. Gidney·M. Giustina·R. Graff·T. Huang·E. Jeffrey·J. Kelly·P. V. Klimov·F. Kostritsa·D. Landhuis·E. Lucero·M. McEwen·A. Megrant·X. Mi·J. Mutus·M. Neeley·C. Neill·E. Ostby·P. Roushan·D. Sank·K. J. Satzinger·A. Vainsencher·T. White·J. Yao·P. Yeh·A. Zalcman·H. Neven·V. N. Smelyanskiy·John M. Martinis
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Abstract

We demonstrate diabatic two-qubit gates with Pauli error rates down to $4.3(2)\cdot 10^{-3}$ in as fast as 18 ns using frequency-tunable superconducting qubits. This is achieved by synchronizing the entangling parameters with minima in the leakage channel. The synchronization shows a landscape in gate parameter space that agrees with model predictions and facilitates robust tune-up. We test both iSWAP-like and CPHASE gates with cross-entropy benchmarking. The presented approach can be extended to multibody operations as well.

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R. Barends, C. M. Quintana, A. G. Petukhov, Yu Chen, D. Kafri, K. Kechedzhi, R. Collins, O. Naaman, S. Boixo, F. Arute, K. Arya, D. Buell, B. Burkett, Z. Chen, B. Chiaro, A. Dunsworth, B. Foxen, A. Fowler, C. Gidney, M. Giustina, R. Graff, T. Huang, E. Jeffrey, J. Kelly, P. V. Klimov, F. Kostritsa, D. Landhuis, E. Lucero, M. McEwen, A. Megrant, X. Mi, J. Mutus, M. Neeley, C. Neill, E. Ostby, P. Roushan, D. Sank, K. J. Satzinger, A. Vainsencher, T. White, J. Yao, P. Yeh, A. Zalcman, H. Neven, V. N. Smelyanskiy, John M. Martinis. 2019-07-04. Diabatic gates for frequency-tunable superconducting qubits. https://doi.org/10.1103/physrevlett.123.210501

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