Understanding Error Sensitivity of Quantum Circuits

Quantum computing is an emerging technology that is poised to revolutionize computational capabilities. However, errors from environmental noise and imperfect hardware can significantly affect the fidelity of the computational results of quantum circuits. In this paper, we put forth a hypothesis that similar to classical computers, not all errors have the same effect on the outputs. To study the error impact at different qubits and at different gates, we leverage the fault injection methodology from a recently proposed framework, QuFI [1], which was designed to produce a quantum vulnerability factor (QVF) heatmap based on all possible fault injections. In our work, we use a similar fault injection approach but focus on the impact of errors at different regions of a circuit. Then, we propose to apply error mitigation techniques selectively to protect the most vulnerable regions of a circuit so as to reduce the overhead of error mitigation schemes.