Current advancements in technology have focused the attention of the quantum
computing community toward exploring the potential of near-term devices whose
computing power surpasses that of classical computers in practical
applications. An unresolved central question revolves around whether the
inherent noise in these devices can be overcome or whether any potential
quantum advantage would be limited. There is no doubt that crosstalk is one of
the main sources of noise in noisy intermediate-scale quantum (NISQ) systems,
and it poses a fundamental challenge to hardware designs. Crosstalk between
parallel instructions can corrupt quantum states and cause incorrect program
execution. In this study, we present a comprehensive analysis of the crosstalk
error effect on NISQ computers. Our approach is extremely straightforward and
practical for characterizing the crosstalk error of various multi-qubit
devices. In particular, we combine the randomized benchmarking (RB) and
simultaneous randomized benchmarking (SRB) protocol to characterize the
crosstalk error from the correlation controlled-NOT (CNOT) gate. We demonstrate
this protocol experimentally on 5- \& 7-qubit devices. Our results demonstrate
the crosstalk error model of two different IBM quantum devices over the
experimental week and compare the error variation against the machine, number
of qubits, quantum volume, processor, and topology of the IBM quantum devices.
We then confirm the improvement in the circuit fidelity on different benchmarks
by up to 3.06x via inserting an instruction barrier, as compared with an IBM
quantum noisy device which offers near-optimal crosstalk mitigation in
practice. Most importantly, we provide insight to ensure that the quantum
operation can perform its quantum magic undisturbed.

量子计算的关键问题是如何解决噪声和串扰错误，本研究通过实验分析了 IBM 量子设备上的串扰错误模型，并提出一种插入指令屏障的方法以显著改善电路准确性。