Dynamical decoupling in two-qubit interactions

Tunable coupler enables new degrees of freedom in controlling qubits, meanwhile it introduces an additional decohering channel. In this talk, we demonstrate extending dynamical decoupling techniques to a multiqubit system including a tunable coupler, successfully suppressing low-frequency noise and elongating decoherence time. Various dynamical-decoupling sequences including spin echo, CPMG and PDD are implemented. In particular, PDD sequences are effective in correcting pulse errors as well. Noise analysis shows flux noise in our system has a 1/f spectrum plus additional low frequency components.