Qubits

Qubits or quantum bits are the fundamental building block for quantum information processes. Whereas conventional computers store and process data as a series of ‘1’s and ‘0’s, quantum computers use the properties of a quantum system, such as the polarization of a photon or the spin of an electron.

Latest Research and Reviews

  • Research |

    Many-body localization—a phenomenon where an isolated system fails to reach thermal equilibrium—has been studied with a programmable quantum processor, which reveals the crucial role played by the initial energy on the onset of localization.

    • Qiujiang Guo
    • , Chen Cheng
    • , Zheng-Hang Sun
    • , Zixuan Song
    • , Hekang Li
    • , Zhen Wang
    • , Wenhui Ren
    • , Hang Dong
    • , Dongning Zheng
    • , Yu-Ran Zhang
    • , Rubem Mondaini
    • , Heng Fan
    •  & H. Wang
  • Research |

    A fundamental superconducting qubit is introduced: ‘blochnium’ is dual to the transmon, relies on a circuit element called hyperinductance, and its fundamental physical variable is the quasicharge of the Josephson junction.

    • Ivan V. Pechenezhskiy
    • , Raymond A. Mencia
    • , Long B. Nguyen
    • , Yen-Hsiang Lin
    •  & Vladimir E. Manucharyan
    Nature 585, 368-371
  • Research |

    A deterministic correction of errors caused by qubit loss or leakage outside the computational space is demonstrated in a trapped-ion experiment by using a minimal instance of the topological surface code.

    • Roman Stricker
    • , Davide Vodola
    • , Alexander Erhard
    • , Lukas Postler
    • , Michael Meth
    • , Martin Ringbauer
    • , Philipp Schindler
    • , Thomas Monz
    • , Markus Müller
    •  & Rainer Blatt
    Nature 585, 207-210
  • Research |

    Ionizing radiation from environmental radioactivity and cosmic rays increases the density of broken Cooper pairs in superconducting qubits, reducing their coherence times, but can be partially mitigated by lead shielding.

    • Antti P. Vepsäläinen
    • , Amir H. Karamlou
    • , John L. Orrell
    • , Akshunna S. Dogra
    • , Ben Loer
    • , Francisca Vasconcelos
    • , David K. Kim
    • , Alexander J. Melville
    • , Bethany M. Niedzielski
    • , Jonilyn L. Yoder
    • , Simon Gustavsson
    • , Joseph A. Formaggio
    • , Brent A. VanDevender
    •  & William D. Oliver
    Nature 584, 551-556

News and Comment

  • News and Views |

    Systems of neutral atoms are gradually gaining currency as a promising candidate for realizing large-scale quantum computing. The achievement of a record-high fidelity in quantum operation with alkaline-earth Rydberg atoms is a case in point.

    • Wenhui Li
    Nature Physics 16, 820-821
  • News and Views |

    Single rare-earth ions are hard to observe and even harder to use as qubits. However, with the help of coupling to an optical cavity and clever engineering of selection rules, a big step has been taken to establish their new role in the quantum world.

    • Roman Kolesov
    •  & Jörg Wrachtrup
    Nature Physics 16, 503-504
  • Research Highlights |

    Decoherence in quantum systems compromises the quantum information processing. However, in molecular systems, coherence is not completely lost and residual coherence can provide important information to guide the design of efficient molecular qubits.

    • Gabriella Graziano
  • News and Views |

    Qubits cannot exist without nonlinearity, but nonlinear elements in superconducting circuits lead to losses. A superconducting qubit has now been realized by nonlinearly coupling two microwave resonators, offering the promise of long coherence times.

    • Gerhard Kirchmair
    Nature Physics 16, 127-128
  • News and Views |

    Non-Hermitian systems with gain and loss give rise to exceptional points with exceptional properties. An experiment with superconducting qubits now offers a first step towards studying these singularities in the quantum domain.

    • Stefan Rotter
    Nature Physics 15, 1214-1215