Low-frequency and Microwave Crosstalk in Superconducting Qubits

Efforts to achieve high-fidelity gates across coupled qubit arrays are complicated by crosstalk of control signals. Low-frequency crosstalk leads to unintended bias shifts of tunable qubits, while crosstalk at microwave frequencies can induce spurious qubit rotations. Here, we describe the characterization of crosstalk in multiqubit arrays over a range of frequencies from dc to the qubit operating frequency. We discuss strategies for mitigating crosstalk at both the hardware and software level.