Quantum memory with near-millisecond coherence in circuit QED

Matthew Reagor (1) , Wolfgang Pfaff (1) , Christopher Axline (1) , Reinier W. Heeres (2, 1) , Nissim Ofek (1) , Katrina Sliwa (1) , Eric Holland (1) , Chen Wang (1) , Jacob Blumoff (1) , Kevin Chou (1) , Michael J. Hatridge (1) , Luigi Frunzio (1) , Michel H. Devoret (1) , Liang Jiang (1) , Robert J. Schoelkopf (1)

1 Departments of Applied Physics [New Haven]
2 QUANTRONICS - Quantronics Group

Significant advances in coherence have made superconducting quantum circuits a viable platform for fault-tolerant quantum computing. To further extend capabilities, highly coherent quantum systems could act as quantum memories for these circuits. A useful quantum memory must be rapidly addressable by qubits, while maintaining superior coherence. We demonstrate a novel supercon-ducting microwave cavity architecture that is highly robust against major sources of loss that are encountered in the engineering of circuit QED systems. The architecture allows for near-millisecond storage of quantum states in a resonator while strong coupling between the resonator and a trans-mon qubit enables control, encoding, and readout at MHz rates. The observed coherence times constitute an improvement of almost an order of magnitude over those of the best available super-conducting qubits. Our design is an ideal platform for studying coherent quantum optics and marks an important step towards hardware-efficient quantum computing with Josephson junction-based quantum circuits.

Domaines: Physique [physics]

Matthew Reagor, Wolfgang Pfaff, Christopher Axline, Reinier W. Heeres, Nissim Ofek, et al.. Quantum memory with near-millisecond coherence in circuit QED. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2016, 94 (1), ⟨10.1103/PhysRevB.94.014506⟩. ⟨cea-01485238⟩