Mitigating Crosstalk on Quantum Computers via Digital Precompilation

Crosstalk errors have been a bane for experimentalists designing quantum computers for more than a decade. Fast two-qubit gates require spatially or spectrally nearby qubits, but such qubits are intrinsically more difficult to address individually. During this talk, we describe a scalable framework for modeling crosstalk effects on quantum information processors. We show how to apply optimal control techniques to tune up arbitrary high-fidelity parallel operations with substantial local and nonlocal crosstalk. We report on experimental data that validates the practicability of our work. These results show that instead of engineering away undesirable interactions during fabrication, chip designers should focus on removing other sources of errors and mitigate such effects with software through careful characterization and control optimization.