Frequency Adjustable Resonator as a Tunable Coupler for Xmon Qubits

We propose a scheme of tunable coupler based on frequency adjustable resonator for scalable quantum integrated circuits. One side the T-shape quarter-wave is short to ground through DC SQUID, which used tune coupler. In other with two open ends, either end capacitively couples different Xmon qubit, determines effective coupling between qubits. The fundamental mode dominates interaction qubits and functions as switch off/on qubit–qubit interaction. required external magnetic flux coupler’s switching off affected by asymmetry degree can help choose better noise environment (of qubits) induced reduce direct qubits, should be an important way suppress ZZ crosstalk realize high-fidelity gates. SQUID several millimeters away from in principle creates less noises compared transmon-type