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Compiling Arbitrary Single-Qubit Gates Via the Phase-Shifts of Microwave Pulses

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 Added by Dawei Ding
 Publication date 2021
  fields Physics
and research's language is English




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Realizing an arbitrary single-qubit gate is a precursor for many quantum computational tasks, including the conventional approach to universal quantum computing. For superconducting qubits, single-qubit gates are usually realized by microwave pulses along drive or flux lines. These pulses are calibrated to realize a particular single-qubit gate. However, it is clearly impractical to calibrate a pulse for every possible single-qubit gate in $SU(2)$. On the other hand, compiling arbitrary gates using a finite universal gate set will lead to unacceptably low fidelities. Here, we provide a compilation scheme for arbitrary single-qubit gates for which the three real parameters of the gate directly correspond to the phase shifts of microwave pulses, which can be made extremely accurate experimentally, that is also compatible with any two-qubit gate. Furthermore, we only require the calibration of the $X_pi$ and $X_{frac pi 2}$ pulses, gates that are already necessary for tasks such as Clifford-based randomized benchmarking as well as measuring the $T_1$ and $T_2$ decoherence parameters.

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