Quantum Teleportation of the Entangled Superconducting Qubits via LC Resonators

Quantum teleportation plays a milestone role in recent quantum information science and technologies. On the other hand, superconducting (SC) qubits characterized by their potential flexibility, tunability, scalability and robust control, all arising from their possible coupling to external fields, are of considerable attention in the quantum information field of research. Motivated from the above-mentioned facts, in this paper we aim to propose a teleportation scheme for an unknown entangled state of two SC qubits from Alice’s lab to Bob’s lab. To do this task, we introduce a scheme using SC qubits wherein the couplings of SC qubits with each other and with LC resonators are simply tunable by applying appropriate external magnetic fields. Due to the necessity of an appropriate entangled channel in the teleportation processes, we first implement the Hadamard and CNOT gates on three SC qubits, which are initially prepared in their vacuum states, by which we are able to generate the GHZ states that will be used as the entangled channel in our proposal. In the continuation, an effective Hamiltonian of the interaction between two SC qubits is considered via appropriately implementing the external fields in Alice’s lab. Next, two interactions between LC resonators and SC qubits are performed beyond the rotating wave approximation to eliminate the undesired states. Then, to achieve the main purpose of paper, the result of some proper measurements on LC resonators and SC qubits in Alice’s lab is classically informed to Bob. At last, by applying phase gate and Pauli-Z ( σ z ) gate on SC qubits in Bob’s lab, the unknown entangled state of the two SC qubits in Alice’s lab is appropriately teleported to the state of SC qubits in Bob’s lab. Interestingly, it is finally observed that, the goal of the paper is successfully accessed with maximum possible fidelity, 1, very clearly above the classical limit, and satisfactorily acceptable value of success probability 0.5. Our work constitutes a significant step towards the realization of quantum repeaters for quantum communications and broadens the tool set for quantum information processing with SC qubits and circuits.