Physics articles within Nature Communications

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  • Article |

    Spin liquids are states of matter in which the constituent spins of a magnet are highly correlated yet fluctuate strongly down to millikelvin temperatures. Here the authors report torque magnetometry measurements of the Mott insulator EtMe3Sb[Pd(dmit)2]2and find it displays an ungapped quantum spin liquid state.

    • D. Watanabe
    • , M. Yamashita
    •  & Y. Matsuda
  • Article
    | Open Access

    Achieving spin separation of charged particles in non-uniform magnetic fields is hindered by the Lorentz force. Kohdaet al. demonstrate spin separation in a semiconductor nanostructure by exploiting the effective magnetic field arising from the spin–orbit interaction and achieve highly polarized spin currents.

    • Makoto Kohda
    • , Shuji Nakamura
    •  & Junsaku Nitta
  • Article
    | Open Access

    A signature of the Dirac-like physics of charge carriers in graphene is the occurrence of an anomalous Hall effect, resulting in a quantization of the Landau levels. Guoet al. observe Landau levels of Dirac fermions in potassium-intercalated graphite arising in the absence of an applied magnetic field.

    • Donghui Guo
    • , Takahiro Kondo
    •  & Junji Nakamura
  • Article
    | Open Access

    Quantum metrology employs the properties of quantum states to further enhance the accuracy of some of the most precise measurement schemes to date. Here, a method for estimating the upper bounds to achievable precision in quantum-enhanced metrology protocols in the presence of decoherence is presented.

    • Rafał Demkowicz-Dobrzański
    • , Jan Kołodyński
    •  & Mădălin Guţă
  • Article |

    Insulators can be classified according to the kind of electronic interactions they are dominated by. Hellmannet al. used time- and angle-resolved photoelectron spectroscopy to determine the dominant interactions in a series of transition metal dichalcogenides.

    • S. Hellmann
    • , T. Rohwer
    •  & K. Rossnagel
  • Article |

    The coil-globule transition undergone by polymers in solution delineates a transition from expanded coils to collapsed globules, depending on the polarity of the solvent. This study examines the influence of vibrational entropy on the transition, and finds it can induce a crossover from a second-order to a first-order transition.

    • Carlo Maffi
    • , Marco Baiesi
    •  & Paolo De Los Rios
  • Article |

    The spin Hall effect and its inverse allow conversion between charge and spin currents in both magnetic and nonmagnetic materials. Weiet al.observe an anomaly in the temperature dependence of the inverse spin Hall effect, which suggests that it can also be used as a sensor for very small magnetic moments.

    • D.H. Wei
    • , Y. Niimi
    •  & Y. Otani
  • Article |

    Frequency comb synthesizers are important for metrology, but they have been difficult to use as frequency rulers in the terahertz region due to their low power. Consolinoet al. phase-lock a quantum cascade laser to a free-space-propagating terahertz comb, demonstrating that they can overcome this limitation.

    • L. Consolino
    • , A. Taschin
    •  & P. De Natale
  • Article
    | Open Access

    Blind quantum computation is a protocol that permits an algorithm, its input and output to be kept secret from the owner of the computational resource doing the calculation. Morimae and Fujii propose a strategy for topologically protected fault-tolerant blind quantum computation that is robust to environmental noise.

    • Tomoyuki Morimae
    •  & Keisuke Fujii
  • Article |

    One of the obstacles to improving the efficiency of organic photovoltaic solar cells is the recombination of polaron pairs at the interface between donor and acceptor molecules. By doping cells with galvinoxyl radicals, Zhanget al. demonstrate a mechanism that overcomes this problem via a spin-flip process.

    • Ye Zhang
    • , Tek P. Basel
    •  & Z. Valy Vardeny
  • Article
    | Open Access

    Multi-partite entanglement is essential not only to understand large quantum ensembles but also to build useful quantum technologies. Armstronget al. demonstrate multimode entanglement of up to eight modes using programmable virtual networks based on linear optics that can be switched in real time.

    • Seiji Armstrong
    • , Jean-François Morizur
    •  & Hans-A. Bachor
  • Article |

    Signal modulation is a mechanism which embeds an information-carrying signal into a carrier wave to broadcast information and is essential for high-speed communication. Zhonget al. report a flexible, transparent all-graphene modulator circuit performing quaternary modulation schemes with only two transistors.

    • Seunghyun Lee
    • , Kyunghoon Lee
    •  & Zhaohui Zhong
  • Article |

    Metallic nanoantennas can be used to enhance and tailor the photoluminescence effects in small-scale devices. Huanget al.design combined nanoantenna electrodes for quantum well nanoscale light-emitting diodes, to both inject charge and control the electroluminescence properties.

    • Kevin C.Y. Huang
    • , Min-Kyo Seo
    •  & Mark L. Brongersma
  • Article |

    Precise qubit manipulation is essential in quantum computation; however errors can occur from fluctuations in the magnetic field. Wanget al. propose a robust scheme for universal control of qubits in a semiconductor double quantum dot, cancelling leading orders of error in field gradient variation.

    • Xin Wang
    • , Lev S. Bishop
    •  & S. Das Sarma
  • Article |

    Understanding ultrafast demagnetisation is key to manipulating magnetic structures on fast timescales, yet laser sources limit the attainable spatial resolution. Here, a soft X-ray high harmonic source enables a high temporal and spatial resolution study of domain demagnetisation in [Co/Pt]30multilayer films.

    • Boris Vodungbo
    • , Julien Gautier
    •  & Jan Lüning
  • Article
    | Open Access

    Optomechanical systems allow for the exploration of macroscopic behaviour at or near the quantum limit. Masselet al. use micromechanical resonators to study the hybridisation of one photonic and two phononic modes with phonon numbers down to 1.8, showing a coupling between all three degrees of freedom.

    • Francesco Massel
    • , Sung Un Cho
    •  & Mika A. Sillanpää
  • Article
    | Open Access

    Along with its electronic characteristics, the spin properties of graphene have recently received increasing attention in the context of spintronic applications. Using microwave radiation, Maniet al. identify resistively detected spin resonance in monolayer and trilayer graphene sheets and extract the value for the Landé g-factor.

    • Ramesh G. Mani
    • , John Hankinson
    •  & Walter A. de Heer
  • Article
    | Open Access

    Measuring the entanglement between down-converted photons is central to many quantum optical experiments, and is normally performed by scanning detectors stepwise across a plane. Edgaret al. use a CCD camera to measure the entire entangled light field, finding strong correlations in position and momentum.

    • M.P. Edgar
    • , D.S. Tasca
    •  & M.J. Padgett
  • Article
    | Open Access

    Light-matter interactions are generally dominated by electric fields and electric-dipole transitions. This study, however, quantifies magnetic contributions to light emission and so exploits the strong natural magnetic-dipole transitions in lanthanide ions to measure optical-frequency magnetic fields.

    • Tim H. Taminiau
    • , Sinan Karaveli
    •  & Rashid Zia
  • Article |

    Topologically protected states of matter are receiving widespread attention owing to their unusual electronic properties. Using numerical simulations, this study predicts that tin telluride is a physical realization of a new class of materials termed topological crystalline insulators.

    • Timothy H. Hsieh
    • , Hsin Lin
    •  & Liang Fu
  • Article |

    The Kondo coupling causes electron mass enhancement in rare earth materials, but not in otherd electron systems. Shimizu et al. report on the combination of frustrated spin liquid and strong Hund's coupling in a vanadium spinel as a mechanism for the microscopic origin of heavy dfermions in transition metals.

    • Yasuhiro Shimizu
    • , Hikaru Takeda
    •  & Hidenori Takagi
  • Article
    | Open Access

    The realization of wafer-scale graphene electronics is envisaged to open up the route to the use of graphene in mainstream electronics. Hertelet al.take a step in this direction by fabricating a transistor with a SiC channel and graphene electrodes, with excellent performance up to megahertz frequencies.

    • S. Hertel
    • , D. Waldmann
    •  & H.B. Weber
  • Article |

    Controlling the behaviour of single molecules on electrode interfaces is crucial for the development of molecular spintronics. This study reports spin-polarized scanning tunnelling microscopy data of the spin-split molecular orbitals of a single-molecule magnet adsorbed on a cobalt surface.

    • Jörg Schwöbel
    • , Yingshuang Fu
    •  & Roland Wiesendanger
  • Article
    | Open Access

    Quantum communication promises important advances in information and communication technology, yet it suffers from alignment sensitivity. Here, an alignment-free approach is demonstrated using liquid crystal devices, allowing for broader applications, including satellites.

    • Vincenzo D'Ambrosio
    • , Eleonora Nagali
    •  & Fabio Sciarrino
  • Article |

    X-ray free-electron lasers offer a wealth of possibilities for future diffraction studies, but variations in successive pulses mean the wavefront is not well defined. Rutishauseret al. use grating interferometry to characterize the wavefronts shot to shot, both in situand under operating conditions.

    • Simon Rutishauser
    • , Liubov Samoylova
    •  & Christian David
  • Article
    | Open Access

    The iron pnictides are a class of superconductors that have received widespread interest in recent years. By doping the prototypical material LaFeAsO with hydrogen, this study reveals the existence of a second superconducting dome at higher doping ranges, which arises due to orbital fluctuations.

    • Soshi Iimura
    • , Satoru Matsuishi
    •  & Hideo Hosono
  • Article |

    Chiral metamaterials present interesting ways to manipulate and distinguish between different circular polarizations of light. Zhanget al. realize chiral metamaterials that exhibit photoinduced switching between left- and right-handed circular polarization interactions at terahertz frequencies.

    • Shuang Zhang
    • , Jiangfeng Zhou
    •  & Xiang Zhang
  • Article |

    Single electron pumps have been proposed as potential candidates for redefining the ampere. This study reports measurements of the quantized current flowing through a semiconductor electron pump with a precision that makes a substantial step towards establishing a direct metric for electrical currents.

    • S.P. Giblin
    • , M. Kataoka
    •  & D.A. Ritchie
  • Article |

    The ability to manipulate single charges is a key requisite for novel nanoelectronic devices. Allenet al. show how to electrostatically confine electrons in suspended bilayer graphene quantum dots by local control of the graphene band structure.

    • M. T. Allen
    • , J. Martin
    •  & A. Yacoby
  • Article |

    The SrTiO3/LaAlO3 system is widely studied because it forms a two-dimensional electron gas at the interface. This study investigates the effects of diluting the LaAlO3 layer with SrTiO3, and finds that the threshold thickness required for the onset of conductivity scales inversely with the fraction of LaAlO3, suggesting an intrinsic origin for the electron gas.

    • M.L. Reinle-Schmitt
    • , C. Cancellieri
    •  & P.R. Willmott
  • Article |

    Absorption imaging relies on the capture of photons by an object to create intensity contrasts, allowing for the visualization of small quantum systems. Streedet al. demonstrate the first absorption imaging of an isolated ytterbium ion, with contrast at the limit of semiclassical theory.

    • Erik W. Streed
    • , Andreas Jechow
    •  & David Kielpinski
  • Article |

    Scanning probe microscopy and related techniques rely on the availability of very sharp tips. Here, a sharpening technique based on field-directed sputtering is demonstrated, resulting in ultrasharp metallic tips for use in scanning tunnelling microscopy as well as atomic-scale lithographic experiments.

    • S.W. Schmucker
    • , N. Kumar
    •  & J.W. Lyding
  • Article |

    Controlling nuclear spin patterns is important to manage decoherence and control electron spin currents in spintronic devices. This study demonstrates the optical creation of rewritable patterns of nuclear polarization in gallium arsenide without ferromagnets, lithographic patterning or field gradients.

    • Jonathan P. King
    • , Yunpu Li
    •  & Jeffrey A. Reimer
  • Article
    | Open Access

    Understanding localization and delocalization phenomena is important for studying wave propagation in many types of disordered photonic systems. Here, a theoretical study of one-dimensional photonic crystal structures reveals the importance of Fano interference in wave transport in the presence of disorder.

    • Alexander N. Poddubny
    • , Mikhail V. Rybin
    •  & Yuri S. Kivshar
  • Article
    | Open Access

    Graphene's remarkable properties make it ideal for optoelectronic devices, and its two-dimensional nature enables its integration with photonic structures. By combining a graphene transistor with a planar microcavity, Engelet al. control the spectrum of the photocurrent and the light emitted by the device.

    • Michael Engel
    • , Mathias Steiner
    •  & Ralph Krupke
  • Article |

    Spin ice is a state of matter that occurs in certain rare earth magnets with a pyrochlore structure. Here it is shown theoretically that, in conjunction with the magnetic monopoles observed in previous experiments, spin ice can also host electric dipoles.

    • D.I. Khomskii
  • Article
    | Open Access

    Nanocrystal quantum dots can exhibit photoluminescence blinking, where the intensity of the emitted light fluctuates due to random charging and discharging. Gallandet al.study thick shell nanocrystals and find that the photoluminescence lifetime can also undergo blinking, without intensity changes.

    • Christophe Galland
    • , Yagnaseni Ghosh
    •  & Victor I. Klimov
  • Article |

    Ink-jet printing methods are an attractive approach to nanofabrication, where electrohydrodynamic control allows for flexible and cheap fabrication. Here, a new approach is presented using electrostatic nanodroplet autofocussing to produce high aspect ratio nanoscale structures like plasmonic nanoantennas.

    • P. Galliker
    • , J. Schneider
    •  & D. Poulikakos
  • Article
    | Open Access

    Magnetometers based on organic magnetoresistance are limited by narrow sensitivity ranges, degradation and temperature fluctuations. Bakeret al. demonstrate a magnetic resonance-based organic thin film magnetometer, which overcomes these drawbacks by exploiting the metrological nature of magnetic resonance.

    • W.J. Baker
    • , K. Ambal
    •  & C. Boehme
  • Article
    | Open Access

    High-intensity laser-plasma ion generation is promising as a compact proton source for applications like ion beam therapy. Using a femtosecond table-top laser system, Zeilet al. show that protons efficiently gain energy in the pre-thermal intra-pulse phase of the generation process.

    • K. Zeil
    • , J. Metzkes
    •  & U. Schramm
  • Article |

    Topological phases are unusual states of matter whose properties are robust against small perturbations. Using a photonic quantum walk system, Kitagawaet al. simulate one-dimensional topological phases and reveal novel topological phenomena far from the static or adiabatic regimes.

    • Takuya Kitagawa
    • , Matthew A. Broome
    •  & Andrew G. White