During quantum circuit execution, there is a high probability of having idle qubits. In superconducting devices, it has been shown that idle qubits can be almost ten times more subject to errors if adjacent qubits operate simultaneously, which introduces “idle error” or decoherence error.

How to reduce idle error? This work explores dynamical decoupling (DD) as a quantum error mitigation technique.

DD inserts a series of pulses periodically to the idle qubits and returns the qubits to their original state. Different DD strategies exist; however, the impact of different DD sequences on specific quantum algorithms remains unknown. Moreover, can DD combined with pulse-level optimization methods, can be used to further improve circuit fidelity?

We explore these questions in our recent work with PhD student Siyuan Niu published at IEEE Transactions on Quantum Engineering.