Quantum switch for coupling highly detuned superconducting qubits

• Published in: Physics letters. A Vol. 382; no. 37; pp. 2626 - 2631
• Main Authors: Xie, Ji-kun, Ma, Sheng-li, Yang, Zhi-peng, Li, Zhen, Li, Fu-li
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 22.09.2018
• Subjects: Quantum entanglement; Quantum state transfer; Superconducting qubit; Quantum state transfer; Superconducting qubit; Quantum entanglement
• ISSN: 0375-9601; 1873-2429
• DOI: 10.1016/j.physleta.2018.07.042

We propose to implement a quantum switch scheme for coupling highly detuned superconducting qubits connected by a gap-tunable bridge qubit. By modulating the frequency of the bridge qubit, it can be used as a coupler to switch on/off and adjust the coupling strength between the initially non-interaction qubits. It is shown that the proposals of quantum information transfer and quantum entangled gate between two highly detuned qubits can be implemented with high fidelity. Moreover, we extend the case of coupling the switch to multiple qubits for the generation of W states. The advantages of our scheme are that it eliminates the need for tuning the gaps of the qubits and the cross-talk interaction is greatly suppressed. The influence of decoherence and parameter variation is also investigated by numerical simulation, which suggests that the present scheme is feasible in current experiment. •The quantum switch scheme for coupling highly detuned superconducting qubits is proposed.•Quantum information transfer and entanglement between two qubit can be implemented with high fidelity.•We also present the generation of multi-qubit W state.