Volume 9 Issue 11, November 2013

Volume 9 Issue 11

A quantum gas trapped in an optical lattice of triangular symmetry can now be driven from a paramagnetic to an antiferromagnetic state by a tunable artificial magnetic field. Article p738 IMAGE: ROBERT HPPNER COVER DESIGN: ALLEN BEATTIE

Editorial

  • Editorial |

    Recent reforms of the Russian Academy of Sciences have caused controversy, and the benefits of the changes are debatable. But what is clear is that proper investment in science must become a priority for Russia's government.

Commentary

  • Commentary |

    A new law for reforming the Russian Academy of Sciences threatens the very future of Russian science itself.

    • Sergei M. Stishov

Perspective

  • Perspective |

    The latest data from the Planck satellite have consolidated our understanding of the cosmic microwave background and the early Universe — except for some large-angle anomalies. These effects could be accounted for by invoking SU(2) gauge symmetry for photon propagation.

    • Ralf Hofmann

Thesis

Books and Arts

Research Highlights

  • Research Highlights |

    The Nobel Prize in Physics 2013 has been awarded to François Englert and Peter Higgs "for the theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles, and which recently was confirmed through the discovery of the predicted fundamental particle, by the ATLAS and CMS experiments at CERN's Large Hadron Collider".

    • Alison Wright
  • Research Highlights |

    • Bart Verberck
  • Research Highlights |

    • Abigail Klopper

News and Views

  • News & Views |

    Alice does not have a quantum computer so she delegates a computation to Bob, who does own one. But how can Alice check whether the computation that Bob performs for her is correct? An experiment with photonic qubits demonstrates such a verification protocol.

    • Tomoyuki Morimae
  • News & Views |

    When a single atom in a condensate is excited to its Rydberg state, its electron orbit encloses the entire condensate. Such a peculiar quantum system could find practical and fundamental applications in atomic physics and quantum information science.

    • Ennio Arimondo
    •  & Jun Ye
  • News & Views |

    Coupling a single electron level to dissipative leads allows the study of unusual behaviour near a quantum critical point, including the fractionalization of the resonant level into two Majorana fermions.

    • Lucas Peeters
    •  & David Goldhaber-Gordon
  • News & Views |

    Information theory was originally developed to study the fundamental limits of telecommunication. But thanks to recent extensions it can now also be applied to solid-state physics.

    • Renato Renner

Letters

  • Letter |

    The Van Allen radiation belts are two rings of charged particles encircling the Earth. Therefore the transient appearance in 2012 of a third ring between the inner and outer belts was a surprise. A study of the ultrarelativistic electrons in this middle ring reveals new physics for particles above 2 MeV.

    • Yuri Y. Shprits
    • , Dmitriy Subbotin
    • , Alexander Drozdov
    • , Maria E. Usanova
    • , Adam Kellerman
    • , Ksenia Orlova
    • , Daniel N. Baker
    • , Drew L. Turner
    •  & Kyung-Chan Kim
  • Letter |

    BiTeCl is a topological insulator with strong inversion asymmetry, which exhibits bulk charge polarization and pyroelectricity. Such a long-sought topological insulator paves the way for applications involving natural p–n junctions and spintronics.

    • Y. L. Chen
    • , M. Kanou
    • , Z. K. Liu
    • , H. J. Zhang
    • , J. A. Sobota
    • , D. Leuenberger
    • , S. K. Mo
    • , B. Zhou
    • , S-L. Yang
    • , P. S. Kirchmann
    • , D. H. Lu
    • , R. G. Moore
    • , Z. Hussain
    • , Z. X. Shen
    • , X. L. Qi
    •  & T. Sasagawa
  • Letter |

    A nanomechanical interface between optical photons and microwave electrical signals is now demonstrated. Coherent transfer between microwave and optical fields is achieved by parametric electro-optical coupling in a piezoelectric optomechanical crystal, and this on-chip technology could form the basis of photonic networks of superconducting quantum bits.

    • Joerg Bochmann
    • , Amit Vainsencher
    • , David D. Awschalom
    •  & Andrew N. Cleland
  • Letter |

    Real-world networks are rarely isolated. A model of an interdependent network of networks shows that an abrupt phase transition occurs when interconnections between independent networks are added. This study also suggests ways to minimize the danger of abrupt structural changes to real networks.

    • Filippo Radicchi
    •  & Alex Arenas

Articles

  • Article |

    If correlations decay exponentially in a one-dimensional quantum many-body system, then entanglement satisfies an area law. The intuitive explanation for this turns out to be wrong, but the statement is nevertheless true, as demonstrated by a proof based on quantum information theory.

    • Fernando G. S. L. Brandão
    •  & Michał Horodecki
  • Article |

    Can Alice verify the result of a quantum computation that she has delegated to Bob without using a quantum computer? Now she can. A protocol for testing a quantum computer using minimum quantum resources has been proposed and demonstrated.

    • Stefanie Barz
    • , Joseph F. Fitzsimons
    • , Elham Kashefi
    •  & Philip Walther
  • Article |

    A quantum critical point associated with a carbon nanotube quantum dot that is in contact with dissipative leads exhibits striking non-Fermi-liquid properties and anomalous scaling. The dissipative environment enables the comparison of the system under thermal- and non-equilibrium conditions.

    • H. T. Mebrahtu
    • , I. V. Borzenets
    • , H. Zheng
    • , Y. V. Bomze
    • , A. I. Smirnov
    • , S. Florens
    • , H. U. Baranger
    •  & G. Finkelstein
  • Article |

    Emerging sensing and quantum-information technologies based on nitrogen–vacancy centres in diamond require a better understanding of the relaxation mechanisms. A two-dimensional spectroscopy study provides information about the effects of the vibrational bath on the electronic dynamics.

    • V. M. Huxter
    • , T. A. A. Oliver
    • , D. Budker
    •  & G. R. Fleming

Corrigendum