Volume 13 Issue 7, July 2017

Volume 13 Issue 7

An inelastic neutron scattering study of the two-dimensional antiferromagnet Ca2RuO4 reveals evidence for a condensed-matter analogue of the Higgs mode, and its subsequent decay into transverse Goldstone modes.Letter p633; Letter p638IMAGE: ADELA MIKLIKOVA, CEITEC MUCOVER DESIGN: BETHANY VUKOMANOVIC

Editorial

  • Editorial |

    The role of physicists in finance is changing, as quantitative trading opens an exciting alternative to traditional financial modelling, and data science lures would-be 'quants' away. But the void is being steadily filled by a new type of analyst.

Thesis

Books and Arts

Research Highlights

News and Views

  • News & Views |

    Ferroelectricity and superconductivity do not have much in common. Now, a superconducting and a ferroelectric-like state have been found to coexist in a doped perovskite oxide.

    • Marc Gabay
    •  & Jean-Marc Triscone
  • News & Views |

    A device with superconducting contacts connected to graphene in the quantum Hall regime hints at a novel Andreev scattering mechanism.

    • Gleb Finkelstein
    •  & François Amet
  • News & Views |

    The shorter the antenna, the higher the frequency — so what happens when nanoantennas hit optical frequencies? One answer may lead to high-harmonic generation without the need for high-powered lasers.

    • Alexandra Landsman
  • News & Views |

    Solid-state systems capable of simulating the theoretical predictions of condensed matter are in short supply. Demonstrations of electronic Lieb lattices using two different platforms suggest this may be about to change.

    • Dario Bercioux
    •  & Sander Otte
  • News & Views |

    Two studies show evidence that single layers of a transition metal dichalcogenide are two-dimensional topological insulators.

    • Aravind Devarakonda
    •  & Joseph G. Checkelsky
  • News & Views |

    A curious peak in the distribution describing stochastic switching in bacterial motility had researchers confounded. But a careful study performed under varying mechanical conditions has now revealed that the breaking of detailed balance is to blame.

    • Yuhai Tu

Letters

  • Letter |

    An inelastic neutron scattering study of the two-dimensional antiferromagnet Ca2RuO4 reveals evidence for a condensed-matter analogue of the Higgs mode, and its subsequent decay into transverse Goldstone modes.

    • A. Jain
    • , M. Krautloher
    • , J. Porras
    • , G. H. Ryu
    • , D. P. Chen
    • , D. L. Abernathy
    • , J. T. Park
    • , A. Ivanov
    • , J. Chaloupka
    • , G. Khaliullin
    • , B. Keimer
    •  & B. J. Kim
  • Letter |

    The presence of a Higgs amplitude mode is revealed in a two-dimensional spin-half quantum antiferromagnet, C9H18N2CuBr4 by means of neutron scattering.

    • Tao Hong
    • , Masashige Matsumoto
    • , Yiming Qiu
    • , Wangchun Chen
    • , Thomas R. Gentile
    • , Shannon Watson
    • , Firas F. Awwadi
    • , Mark M. Turnbull
    • , Sachith E. Dissanayake
    • , Harish Agrawal
    • , Rasmus Toft-Petersen
    • , Bastian Klemke
    • , Kris Coester
    • , Kai P. Schmidt
    •  & David A. Tennant
  • Letter |

    Slight changes in SrTiO’s nominal composition make it superconducting or ferroelectric. A compositional window for which the two phases exist is now reported; varying the fraction of Ca replacing Sr changes the superconducting critical temperature.

    • Carl Willem Rischau
    • , Xiao Lin
    • , Christoph P. Grams
    • , Dennis Finck
    • , Steffen Harms
    • , Johannes Engelmayer
    • , Thomas Lorenz
    • , Yann Gallais
    • , Benoît Fauqué
    • , Joachim Hemberger
    •  & Kamran Behnia
  • Letter |

    An excited two-level system emits a single photon, but in special circumstances it can emit two. The reason for this unexpected two-photon emission lies with modified Rabi oscillations.

    • Kevin A. Fischer
    • , Lukas Hanschke
    • , Jakob Wierzbowski
    • , Tobias Simmet
    • , Constantin Dory
    • , Jonathan J. Finley
    • , Jelena Vučković
    •  & Kai Müller
  • Letter |

    High-harmonic emission from crystalline silicon can be made ten times brighter by exploiting local plasmonic fields in arrays of nano-antennas.

    • G. Vampa
    • , B. G. Ghamsari
    • , S. Siadat Mousavi
    • , T. J. Hammond
    • , A. Olivieri
    • , E. Lisicka-Skrek
    • , A. Yu Naumov
    • , D. M. Villeneuve
    • , A. Staudte
    • , P. Berini
    •  & P. B. Corkum
  • Letter |

    Individual vacancies in a chlorine monolayer on copper can be manipulated with scanning tunnelling microscopy to engineer artificial lattices that have topologically nontrivial electronic states.

    • Robert Drost
    • , Teemu Ojanen
    • , Ari Harju
    •  & Peter Liljeroth
  • Letter |

    Individual carbon monoxide molecules on a copper surface can be manipulated with scanning tunnelling microscopy to realize an electronic Lieb lattice.

    • Marlou R. Slot
    • , Thomas S. Gardenier
    • , Peter H. Jacobse
    • , Guido C. P. van Miert
    • , Sander N. Kempkes
    • , Stephan J. M. Zevenhuizen
    • , Cristiane Morais Smith
    • , Daniel Vanmaekelbergh
    •  & Ingmar Swart
  • Letter |

    Experiments showing that a single layer of WTe2 can conduct electricity along its edges while insulating in the interior suggests that this material is a two-dimensional topological insulator.

    • Zaiyao Fei
    • , Tauno Palomaki
    • , Sanfeng Wu
    • , Wenjin Zhao
    • , Xinghan Cai
    • , Bosong Sun
    • , Paul Nguyen
    • , Joseph Finney
    • , Xiaodong Xu
    •  & David H. Cobden
  • Letter |

    A combination of photoemission and scanning tunnelling spectroscopy measurements provide compelling evidence that single layers of 1T'-WTe2 are a class of quantum spin Hall insulator.

    • Shujie Tang
    • , Chaofan Zhang
    • , Dillon Wong
    • , Zahra Pedramrazi
    • , Hsin-Zon Tsai
    • , Chunjing Jia
    • , Brian Moritz
    • , Martin Claassen
    • , Hyejin Ryu
    • , Salman Kahn
    • , Juan Jiang
    • , Hao Yan
    • , Makoto Hashimoto
    • , Donghui Lu
    • , Robert G. Moore
    • , Chan-Cuk Hwang
    • , Choongyu Hwang
    • , Zahid Hussain
    • , Yulin Chen
    • , Miguel M. Ugeda
    • , Zhi Liu
    • , Xiaoming Xie
    • , Thomas P. Devereaux
    • , Michael F. Crommie
    • , Sung-Kwan Mo
    •  & Zhi-Xun Shen
  • Letter |

    Picosecond pulses of terahertz radiation induce non-equilibrium electron dynamics in a GaAs quantum Hall system, suppressing the longitudinal resistivity, and giving rise to a quantized transverse component.

    • T. Arikawa
    • , K. Hyodo
    • , Y. Kadoya
    •  & K. Tanaka

Articles

  • Article |

    A superconductor–graphene junction is shown to exhibit the quantum Hall effect, with the chemical potential of the edge state displaying a sign reversal. Such a system could provide a platform for observing isolated non-Abelian anyonic zero modes.

    • Gil-Ho Lee
    • , Ko-Fan Huang
    • , Dmitri K. Efetov
    • , Di S. Wei
    • , Sean Hart
    • , Takashi Taniguchi
    • , Kenji Watanabe
    • , Amir Yacoby
    •  & Philip Kim
  • Article |

    Can short-range repulsion alone bring a system into the ferromagnetic phase? The question is explored by investigating the spin dynamics in a resonantly interacting ultracold Fermi gas, and a Stoner-like ferromagnetic instability is observed.

    • G. Valtolina
    • , F. Scazza
    • , A. Amico
    • , A. Burchianti
    • , A. Recati
    • , T. Enss
    • , M. Inguscio
    • , M. Zaccanti
    •  & G. Roati

Measure for Measure

  • Measure for Measure |

    The path to consistent cgs magnetic units has been long and winding, as is the process of universally adopting SI units. Andreas Trabesinger peeks into the history of the field.

    • Andreas Trabesinger