Spectroscopic Measurements on Error Protected Superconducting Qubit Design Based on Josephson Junction Arrays

ORAL

Abstract

Since the first demonstration of quantum coherence in superconducting qubits, the coherence times of the various designs have undergone a significant improvement. This remarkable evolution is mainly the result of the combination of new qubit designs with reduced sensitivity to external noise, engineered qubit environments, advances in materials and fabrication techniques. An alternative approach to further increase qubit coherence times is to harness potential intrinsic protections of certain superconducting circuits. This is the case in the recently proposed zero-pi qubit [PRA 87, 052306 (2013)]. In this talk we present a qubit design which is based on the zero-pi circuit in a parameter regime which is experimentally achievable by using long Josephson junction arrays. The circuit offers protection against both energy relaxation, due to disjoint support of the qubit subspace and dephasing, due to diminishing flux sensitivity at the sweet points. We describe the symmetric coupling scheme of the qubit used for dispersive read-out and demonstrate the rich energy level spectrum of the device.

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Presenters

  • Andras Gyenis

    Department of Electrical Engineering, Princeton University, Princeton University, Department of Electrical Engineering, Princeton University, Electrical Engineering, Princeton University

Authors

  • Andras Gyenis

    Department of Electrical Engineering, Princeton University, Princeton University, Department of Electrical Engineering, Princeton University, Electrical Engineering, Princeton University

  • Thomas Hazard

    Department of Electrical Engineering, Princeton University, Electrical Engineering, Princeton University

  • Andrei Vrajitoarea

    Department of Electrical Engineering, Princeton University

  • Agustin Di Paolo

    Institut Quantique and Département de Physique, Université de Sherbrooke

  • Peter Groszkowski

    Department of Physics and Astronomy, Northwestern University

  • Alexandre Blais

    Institut quantique and Departement de Physique, Universite de Sherbrooke, Physique, Institut Quantique, University of Sherbrooke, Institut quantique and Department de Physique, Universite de Sherbrooke, Physique, Universite de Sherbrooke, Physics, University of Sherbrooke, Institut quantique and Départment de Physique, Université de Sherbrooke, Institut Quantique and Département de Physique, Université de Sherbrooke, Univ of Sherbrooke, Institut Quantique and Département de Physique, Université de Sherbooke, Institut quantique and Département de Physique, Université de Sherbrooke, Department of Physics, University of Sherbrooke

  • Jens Koch

    Northwestern Univeristy, Department of Physics and Astronomy, Northwestern University, Department of Physics and Astronomy, Northwestern Univ, Department of Physics & Astronomy, Northwestern University, Northwestern University, Physics, Northwestern University

  • Andrew Houck

    Electrical Engineering, Princeton University, Princeton University, Department of Electrical Engineering, Princeton University, Princeton University, Department of Electrical Engineering