Quantum physics

  • Article
    | Open Access

    A silicon nitride microresonator is used for coherent phase modulation of a transmission electron microscope beam, with future applications in combining high-resolution microscopy with spectroscopy, holography and metrology.

    • Jan-Wilke Henke
    • , Arslan Sajid Raja
    •  & Tobias J. Kippenberg
  • Article |

    An ensemble of electron spins is detected by their microwave fluorescence using a superconducting single microwave photon counter, making single-spin electron spin resonance spectroscopy a possible future prospect.

    • Emanuele Albertinale
    • , Léo Balembois
    •  & Emmanuel Flurin
  • Article |

    Magnetically tunable interactions between lithium atoms and barium ions are used to demonstrate and probe Feshbach resonances between atoms and ions, which could have applications in the fields of experimental quantum simulation and fundamental physics.

    • Pascal Weckesser
    • , Fabian Thielemann
    •  & Tobias Schaetz
  • Article
    | Open Access

    Existing techniques for high-resolution imaging of trapped quantum gases are limited to two-dimensional systems, but the approach described here works in three dimensions by magnifying the quantum gas with matter wave optics.

    • Luca Asteria
    • , Henrik P. Zahn
    •  & Christof Weitenberg
  • Article |

    An optical lattice for trapping a Bose–Einstein condensate reported here includes photon-mediated atom–atom interactions that replicate acoustic modes in real crystals.

    • Yudan Guo
    • , Ronen M. Kroeze
    •  & Benjamin L. Lev
  • Article |

    A zero-knowledge proof, which can be used to verify secret information, is reported here with security that is enforced by the laws of special relativity.

    • Pouriya Alikhani
    • , Nicolas Brunner
    •  & Hugo Zbinden
  • Article |

    Fault-tolerant circuits for the control of a logical qubit encoded in 13 trapped ion qubits through a Bacon–Shor quantum error correction code are demonstrated.

    • Laird Egan
    • , Dripto M. Debroy
    •  & Christopher Monroe
  • Article |

    Nonlinearity induced by a single photon is desirable because it can drive power consumption of optical devices to their fundamental quantum limit, and is demonstrated here at room temperature.

    • Anton V. Zasedatelev
    • , Anton V. Baranikov
    •  & Pavlos G. Lagoudakis
  • Article |

    Gold nanoflake pairs form by self-assembly in an aqueous ligand solution and offer stable and tunable microcavities by virtue of equilibrium between attractive Casimir forces and repulsive electrostatic forces.

    • Battulga Munkhbat
    • , Adriana Canales
    •  & Timur O. Shegai
  • Article |

    Laser-free universal control of two trapped-ion qubits using a combination of radiofrequency and microwave magnetic fields achieves some of the highest fidelities ever reported for two-qubit maximally entangled states.

    • R. Srinivas
    • , S. C. Burd
    •  & D. H. Slichter
  • Article
    | Open Access

    A single electromagnetically trapped proton is sympathetically cooled to below ambient temperature by coupling it through a superconducting LC circuit to a laser-cooled cloud of Be+ ions stored in a spatially separated trap.

    • M. Bohman
    • , V. Grunhofer
    •  & S. Ulmer
  • Article
    | Open Access

    A globally chiral atomic superfluid is induced by time-reversal symmetry breaking in an optical lattice and exhibits global angular momentum, which is expected to lead to topological excitations and the demonstration of a topological superfluid.

    • Xiao-Qiong Wang
    • , Guang-Quan Luo
    •  & Zhi-Fang Xu
  • Article |

    Nonlinearity is shown to induce quantized topological transport via soliton motion; specifically, we demonstrate nonlinear Thouless pumping of photons in waveguide arrays with a non-uniformly occupied energy band.

    • Marius Jürgensen
    • , Sebabrata Mukherjee
    •  & Mikael C. Rechtsman
  • Article |

    A programmable quantum simulator with 256 qubits is created using neutral atoms in two-dimensional optical tweezer arrays, demonstrating a quantum phase transition and revealing new quantum phases of matter.

    • Sepehr Ebadi
    • , Tout T. Wang
    •  & Mikhail D. Lukin
  • Article |

    Operating in space, NASA’s Deep Space Atomic Clock, a trapped-ion clock, is shown to have long-term stability and drift that are an order of magnitude better than current space clocks.

    • E. A. Burt
    • , J. D. Prestage
    •  & T. A. Ely
  • Article |

    As a blueprint for high-precision quantum simulation, an 18-qubit algorithm that consists of more than 1,400 two-qubit gates is demonstrated, and reconstructs the energy eigenvalues of the simulated one-dimensional wire to a precision of 1 per cent.

    • C. Neill
    • , T. McCourt
    •  & V. Smelyanskiy
  • Article |

    A Bose-Einstein condensate of molecules is produced by pairing atoms in an atomic condensate; this transition is the bosonic analog of the Bardeen-Cooper-Schrieffer superfluid to BEC crossover in Fermi gases.

    • Zhendong Zhang
    • , Liangchao Chen
    •  & Cheng Chin
  • Article |

    The quantum charge-coupled device architecture is demonstrated, with its various elements integrated into a programmable trapped-ion quantum computer and performing simple quantum operations with state-of-the-art levels of error.

    • J. M. Pino
    • , J. M. Dreiling
    •  & B. Neyenhuis
  • Article
    | Open Access

    A nondestructive detector of photonic qubits, comprising a single 87Rb atom trapped in the centre point of two crossed fibre-based optical resonators, is demonstrated.

    • Dominik Niemietz
    • , Pau Farrera
    •  & Gerhard Rempe
  • Article |

    Using germanium quantum dots, a four-qubit processor capable of single-, two-, three-, and four-qubit gates, demonstrated by the creation of four-qubit Greenberger−Horne−Zeilinger states, is the largest yet realized with solid-state electron spins.

    • Nico W. Hendrickx
    • , William I. L. Lawrie
    •  & Menno Veldhorst
  • Article |

    A reinforcement learning experiment using a programmable integrated nanophotonic processor shows that a quantum communication channel with the environment speeds up the learning process of an agent.

    • V. Saggio
    • , B. E. Asenbeck
    •  & P. Walther
  • Article |

    High-fidelity deterministic quantum state transfer and multi-qubit entanglement are demonstrated in a quantum network comprising two superconducting quantum nodes one metre apart, with each node including three interconnected qubits.

    • Youpeng Zhong
    • , Hung-Shen Chang
    •  & Andrew N. Cleland
  • Article
    | Open Access

    Suitably shaped X-ray pulses are used to coherently steer the quantum dynamics of atoms’ nuclei rather than their electrons, with few-zeptosecond temporal stability of the phase control.

    • Kilian P. Heeg
    • , Andreas Kaldun
    •  & Jörg Evers
  • Article |

    A quantum enhanced search for dark matter that uses vacuum squeezing to overcome the quantum noise limit finds no evidence of dark matter axions in a well motivated mass range.

    • K. M. Backes
    • , D. A. Palken
    •  & H. Wang
  • Article |

    Two logical qubits are encoded in ensembles of four physical qubits through the surface code, then entangled by lattice surgery, which is a protocol for carrying out fault-tolerant operations.

    • Alexander Erhard
    • , Hendrik Poulsen Nautrup
    •  & Thomas Monz
  • Article |

    A chip-scale platform is developed for the conversion of a single microwave excitation of a superconducting qubit into optical photons, with potential uses in quantum computer networks.

    • Mohammad Mirhosseini
    • , Alp Sipahigil
    •  & Oskar Painter
  • Article |

    A many-atom state of trapped 171Yb atoms that are entangled on an optical atomic-clock transition overcomes the standard quantum limit, providing a proof-of-principle demonstration towards entanglement-based optical atomic clocks.

    • Edwin Pedrozo-Peñafiel
    • , Simone Colombo
    •  & Vladan Vuletić
  • Article |

    Spin transport far from equilibrium is studied in a Heisenberg model with adjustable anisotropy realized with coupled ultracold 7Li atoms, and different dynamical regimes are found for positive and negative anisotropies.

    • Paul Niklas Jepsen
    • , Jesse Amato-Grill
    •  & Wolfgang Ketterle