Spectroscopy of superconducting charge qubits coupled by a Josephson inductance

2008/02/04 by T. Yamamoto, Tsuyoshi Yamamoto, Michio Watanabe +10
Computer Science · Physics and Astronomy · #Charge qubit #Condensed matter physics #Coupling (piping) #Flux qubit #Inductance #Inductive coupling #Josephson effect #Magnetic field #Magnetic flux #Materials science #Phase qubit #Physics #Physics of Superconductivity and Magnetism #Pi Josephson junction #Quantum #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum mechanics #Qubit #Superconducting quantum computing #Superconducting tunnel junction #Superconductivity #Voltage #cond-mat.mes-hall #cond-mat.supr-con

paper · pdf · doi:10.1103/physrevb.77.064505

published as Phys. Rev. B 77, 064505 (2008) · Accepted for publication in PRB. 11 pages, 7 figures

arxiv created 2008/02/04 · openalex publication_date 2008/02/11 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We have designed and experimentally implemented a circuit of inductively coupled superconducting charge qubits, where a Josephson junction is used as an inductance, and the coupling between the qubits is controlled by an applied magnetic flux. Spectroscopic measurements on the circuit are in good agreement with theoretical calculations. We observed anticrossings which originate from the coupling between the qubit and the plasma mode of the Josephson junction. Moreover, the size of the anticrossing depends on the external magnetic flux, which demonstrates the controllability of the coupling.

Citations

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