Cavity-mediated cross-cross-resonance gate

  1. Alexey V. Gorshkov,
  2. Daniel Cohen,
  3. Arbel Haim,
  4. Amit Rotem,
  5. Or Golan,
  6. Gihwan Kim,
  7. Andreas Butler,
  8. Connor T. Hann,
  9. Oskar Painter,
  10. Fernando G.S.L. Brandão,
  11. and Alex Retzker
We propose a cavity-mediated gate between two transmon qubits or other nonlinear superconducting elements. The gate is realized by driving both qubits at a frequency that is near-resonant
with the frequency of the cavity. Since both qubits are subject to a cross-resonant drive, we call this gate a cross-cross-resonance gate. In close analogy with gates between trapped-ion qubits, in phase space, the state of the cavity makes a circle whose area depends on the state of the two qubits, realizing a controlled-phase gate. We propose two schemes for canceling the dominant error, which is the dispersive coupling. We also show that this cross-cross-resonance gate allows one to realize simultaneous gates between multiple pairs of qubits coupled via the same metamaterial composed of an array of coupled cavities or other linear mediators.