Parasitic free gate

Implementation of high-performance two-qubit gates is a key factor for scalable quantum computation. However, the state-of-the-art superconducting two-qubit gates are yet far from being perfect due to the parasitic ZZ coupling.  In this paper, we propose a parasitic free (PF) gate to suppress such unwanted interaction in use of the tunable coupler. The gate is operated in two modes: in idle mode the coupler frequency is tuned such that the two qubits are effectively decoupled; in driven mode the coupler frequency is tuned so as to result in a nonzero static ZZ interaction, which later can be cancelled by the dynamical part. Our theory shows that using this method the fidelity of a CR gate is able to achieve the coherence limit.