Article |
Featured
-
-
Article
| Open AccessStable magnetostructural coupling with tunable magnetoresponsive effects in hexagonal ferromagnets
The coupling that occurs between the structural and the magnetic properties of magnetic materials leads to a host of magnetoresponsive effects that are useful for potential technological applications. Here, a strong magnetostructural coupling that persists over a wide temperature range is reported in MnNiGe:Fe alloys.
- Enke Liu
- , Wenhong Wang
- & Frank de Boer
-
Article
| Open AccessElectric-field control of domain wall motion in perpendicularly magnetized materials
The motion of domain walls in magnetic materials characterized by a perpendicular axis of magnetization is a promising means of controlling information in future memory and logic devices. Schellekenset al. show the velocity of domain walls in such systems can be controlled by using an applied electric field.
- A.J. Schellekens
- , A. van den Brink
- & B. Koopmans
-
Article
| Open AccessSuperionic glass-ceramic electrolytes for room-temperature rechargeable sodium batteries
Rechargeable solid-state batteries are promising sources of energy for a range of applications. Hayashiet al. examine the electrochemistry of solid-state sodium batteries, and present an electrolyte that operates at room temperature.
- Akitoshi Hayashi
- , Kousuke Noi
- & Masahiro Tatsumisago
-
Article |
Spin-motive force due to a gyrating magnetic vortex
The electromotive force is a well established phenomenon that is induced by a varying magnetic field. Here, Tanabeet al. report a compelling experimental confirmation of its spin-induced analogue, the spinmotive force.
- K. Tanabe
- , D. Chiba
- & T. Ono
-
Article |
Closed network growth of fullerenes
The formation mechanisms of fullerenes remain unclear. This study shows that fullerenes self-assemble through a closed network growth mechanism in which atomic carbon and C2are incorporated into the growing closed cages.
- Paul W. Dunk
- , Nathan K. Kaiser
- & Harold W. Kroto
-
Article
| Open AccessResonant magnetic exciton mode in the heavy-fermion antiferromagnet CeB6
Resonant magnetic excitations are common in unconventional superconductors, but the mechanism for their formation is elusive. Using inelastic neutron scattering, this study finds similar excitations in the non-superconducting heavy-fermion metal CeB6, suggesting common behaviour between the two ground states.
- G. Friemel
- , Yuan Li
- & D.S. Inosov
-
Article |
Giant nonlinear optical activity in a plasmonic metamaterial
Light propagating in a medium can undergo polarization rotation, an effect that depends on light intensity and chiral properties. Renet al. report polarization rotation in a plasmonic metamaterial with million-fold stronger nonlinearity than that found in natural crystals.
- Mengxin Ren
- , Eric Plum
- & Nikolay I. Zheludev
-
Article
| Open AccessSwitching of macroscopic molecular recognition selectivity using a mixed solvent system
Self-assembly via molecular recognition events is used in the production of functionalized materials. This Article reports that the macroscopic assembly of polyacrylamide gels can be controlled by changing the composition of a mixed solvent system.
- Yongtai Zheng
- , Akihito Hashidzume
- & Akira Harada
-
Article |
Phase fluctuations and the absence of topological defects in a photo-excited charge-ordered nickelate
Time- and momentum-resolved spectroscopy gives dynamical information on complex materials, enabling disentanglement of their coupled degrees of freedom. Using time-resolved X-ray diffraction at a free electron laser, Leeet al. investigate the charge order parameter in a striped nickelate.
- W.S. Lee
- , Y.D. Chuang
- & Z. Hussain
-
Article
| Open AccessEnamel-like apatite crown covering amorphous mineral in a crayfish mandible
The compositional makeup of skeletons and teeth in invertebrates and vertebrates is generally different. This study examines the material composition and properties of freshwater crayfish mandibles and finds, in an unusual case of convergent evolution, that they are composed of an apatite layer that is similar to mammalian enamel.
- Shmuel Bentov
- , Paul Zaslansky
- & Barbara Aichmayer
-
Article
| Open AccessNanotomy-based production of transferable and dispersible graphene nanostructures of controlled shape and size
Current top-down and bottom-up syntheses of graphene nanostructures suffer from low yields or do not produce structures with different and controlled shapes. Here, monodisperse graphene shapes are produced by diamond-edge cutting of pyrolytic graphite followed by exfoliation.
- Nihar Mohanty
- , David Moore
- & Vikas Berry
-
Article |
Transforming moiré blisters into geometric graphene nano-bubbles
Strain engineering has been proposed as a promising strategy for manipulating the electronic properties of graphene. This scanning tunnelling microscopy study demonstrates the feasibility of controlling strain patterns in graphene down to the nanoscale.
- Jiong Lu
- , A.H. Castro Neto
- & Kian Ping Loh
-
Article
| Open AccessGraphene quilts for thermal management of high-power GaN transistors
Electronic and optoelectronic devices based on gallium nitride suffer from self-heating arising as a result of their operation. This study presents and demonstrates a strategy for managing this problem that relies on graphene quilts which dissipate the heat away.
- Zhong Yan
- , Guanxiong Liu
- & Alexander A. Balandin
-
Article |
Tuning the magneto-structural properties of non-porous coordination polymers by HCl chemisorption
Tuning the properties of responsive materials by applying an external stimulus could lead to their application as chemical switches or molecular sensors. Coronadoet al. develop a non-porous one-dimensional coordination polymer, the magnetic properties of which undergo drastic changes on chemisorption of gaseous HCl.
- Eugenio Coronado
- , Mónica Giménez-Marqués
- & Lee Brammer
-
Article
| Open AccessFrequency stabilization in nonlinear micromechanical oscillators
Micromechanical oscillators present a route to miniaturisation of devices and may be used as frequency references or sensitive sensors, but their small size means that they often behave nonlinearly. Antonioet al. demonstrate frequency stabilisation of nonlinear resonators by coupling two vibrational modes.
- Dario Antonio
- , Damián H. Zanette
- & Daniel López
-
Article |
Topological repulsion between domain walls in magnetic nanowires leading to the formation of bound states
The manipulation of domain walls in magnetic nanodevices is a topic of increasing technological relevance. This study examines the interactions that occur between vortex domain walls in permalloy nanowires, and finds that bound states occur between domain walls with opposite magnetic charge.
- Luc Thomas
- , Masamitsu Hayashi
- & Stuart Parkin
-
Article |
Local chiral symmetry breaking in triatic liquid crystals
Studying the structures of dense colloidal systems of anisotropic Brownian particles provides insight into fundamental processes like protein crystallization. Zhaoet al. study the phases of two-dimensional triatic liquid crystals and find that one of them exhibits local chiral-symmetry breaking.
- Kun Zhao
- , Robijn Bruinsma
- & Thomas G. Mason
-
Article |
Non-polydimethylsiloxane devices for oxygen-free flow lithography
Flow lithography is used to synthesize microparticles but relies on polydimethylsiloxane microchannels for oxygen to permeate and inhibit polymerization near channel interfaces. Now, non-polydimethylsiloxane devices have been developed, which allow oxygen-free lithography, increasing the capabilities of flow lithography.
- Ki Wan Bong
- , Jingjing Xu
- & Patrick S. Doyle
-
Article |
Prominent electrochromism through vacancy-order melting in a complex oxide
Electrochromic materials reversibly change their colour upon application of an electric field. Seidelet al. measure the optical properties of doped bismuth ferrite and report the largest electrochromic response for an inorganic material, which they attribute to the melting of oxygen-vacancy ordering.
- J. Seidel
- , W. Luo
- & R. Ramesh
-
Article |
Binary colloidal structures assembled through Ising interactions
The assembly of microscopic particles into macroscopic structures may allow the fabrication of complex materials, but general strategies to provide a wide variety of structures are lacking. Khalilet al. develop a colloidal assembly system, which can be tuned to provide over 20 different pre-programmed structures.
- Karim S. Khalil
- , Amanda Sagastegui
- & Benjamin B. Yellen
-
Article |
Stiffening hydrogels to probe short- and long-term cellular responses to dynamic mechanics
Studying the effects of extracellular matrix stiffening has been impeded because mostin vitromodels are static. Here, dynamic hydrogels are developed that stiffen in the presence of cells and are used to investigate the short-term (minutes-to-hours) and long-term (days-to-weeks) cellular responses to dynamic stiffening.
- Murat Guvendiren
- & Jason A. Burdick
-
Article
| Open AccessStrong-coupling d-wave superconductivity in PuCoGa5 probed by point-contact spectroscopy
The heavy-fermion material PuCoGa5 is characterized by unconventional superconducting properties. By combining point-contact spectroscopy and first-principles calculations, this study reveals a d-wave symmetry in the system's order parameter.
- D. Daghero
- , M. Tortello
- & R. Caciuffo
-
Article |
Atomic-scale evolution of modulated phases at the ferroelectric–antiferroelectric morphotropic phase boundary controlled by flexoelectric interaction
Morphotropic phase boundaries—regions of abrupt structural change and enhanced material response—are of practical importance and are a challenge for the fundamental theory of phase transitions. Here, the ferroelectric–antiferroelectric boundary is studied using atomically resolved mapping in BiFeO3.
- A.Y. Borisevich
- , E.A. Eliseev
- & S.V. Kalinin
-
Article
| Open AccessUltrathin and lightweight organic solar cells with high flexibility
Organic solar cells are promising for technological applications, as they are lightweight and mechanically robust. This study presents flexible organic solar cells that are less than 2 μm thick, have very low specific weight and maintain their photovoltaic performance under repeated mechanical deformation.
- Martin Kaltenbrunner
- , Matthew S. White
- & Siegfried Bauer
-
Article |
Dark acoustic metamaterials as super absorbers for low-frequency sound
Metamaterials can be used to alter the transmission of light or sound, with their tailored structures permitting control over their optical or acoustic properties. Meiet al. present a thin-film acoustic metamaterial that provides efficient absorption of sound over a broad range of wavelengths.
- Jun Mei
- , Guancong Ma
- & Ping Sheng
-
Article |
Graphene-based wireless bacteria detection on tooth enamel
Graphene is characterized by unique physical properties that offer substantial promise, most notably for electronic applications. Mannooret al. present a wireless graphene-based sensor for detecting bacteria on a range of biological tissues.
- Manu S. Mannoor
- , Hu Tao
- & Michael C. McAlpine
-
Article |
Giant spin-dependent thermoelectric effect in magnetic tunnel junctions
The spin-dependent thermal and electrical transport properties of nanostructures are central for future applications of spintronic devices. Here, Linet al. report an enhanced spin-dependent thermoelectric effect in an Al2O3-based magnetic tunnel junction.
- Weiwei Lin
- , Michel Hehn
- & Stéphane Mangin
-
Article
| Open AccessEnhanced electromechanical response of ferroelectrics due to charged domain walls
The piezoelectric materials most commonly used for technological applications contain lead, a toxic element. Slukaet al. identify a mechanism that leads to an enhancement of the dielectric and piezoelectric properties of non-toxic ferroelectrics, due to the presence of charged domain walls.
- Tomas Sluka
- , Alexander K. Tagantsev
- & Nava Setter
-
Article |
Probing charge scattering mechanisms in suspended graphene by varying its dielectric environment
A factor limiting the mobility of charge carriers in graphene, and therefore its use in electronic applications, is the Coulomb scattering due to charged impurities. By exposing graphene devices to a range of non-polar liquids, Newazet al. observe an enhancement of the mobility due to screening.
- A.K.M. Newaz
- , Yevgeniy S. Puzyrev
- & Kirill I. Bolotin
-
Article |
Integrated photosystem II-based photo-bioelectrochemical cells
The photosynthetic reaction centres, photosystems I and II, have been investigated for the light-induced generation of fuels and electrical power. Now, Yehezkeliet al. report a photobiofuel cell that generates electricity upon irradiation of photosystem II-functionalized electrodes in aqueous solutions.
- Omer Yehezkeli
- , Ran Tel-Vered
- & Itamar Willner
-
Article |
Observation of conducting filament growth in nanoscale resistive memories
Resistive switching devices are promising candidates for non-volatile memories. Usingin-situ and ex-situ transmission electron microscopy, Yang et al. present an extensive study of the dynamics of filaments forming across the electrodes of resisting switching devices known as electrochemical metallization memories.
- Yuchao Yang
- , Peng Gao
- & Wei Lu
-
Article |
Perpendicular exchange bias in ferrimagnetic spin valves
Exchange bias is a technologically relevant effect that occurs when thin ferromagnetic films are placed in direct proximity to antiferromagnets. Raduet al. show that an exchange bias occurs at room temperature in ferrimagnetic trilayers, in which the magnetization is aligned perpendicular to the structures.
- F. Radu
- , R. Abrudan
- & H. Zabel
-
Article |
Ultrafast changes in lattice symmetry probed by coherent phonons
Ultrafast excitation offers new routes to controlling material properties on short timescales, but probes are needed to better understand the changes. By studying the phonon spectrum of VO2 in the time domain, Wall et al. find a prompt change in lattice potential after a photoinduced structural transition.
- S. Wall
- , D. Wegkamp
- & M. Wolf
-
Article
| Open AccessCharge state manipulation of qubits in diamond
Point defects in diamond in the form of nitrogen vacancy centres are believed to be promising candidates for qubits in quantum computers. Grotzet al. present a method for manipulating the charge state of nitrogen vacancies using an electrolytic gate electrode.
- Bernhard Grotz
- , Moritz V. Hauf
- & Jose A. Garrido
-
Article |
Organic transistors with high thermal stability for medical applications
Organic electronic devices are promising for many applications, particularly in biomedical research, but are hindered by thermal instability and low melting points. Now, organic thin-film transistors are shown with excellent thermal properties that can withstand medical sterilization processes.
- Kazunori Kuribara
- , He Wang
- & Takao Someya
-
Article |
Room temperature ferromagnetism in Teflon due to carbon dangling bonds
Teflon is a carbon based polymer that cannot be intrinsically ferromagnetic. This study shows that room temperature ferromagnetism can be induced in Teflon tape by applying mechanical stress such as stretching or cutting, which gives rise to dangling carbon bonds.
- Y.W. Ma
- , Y.H. Lu
- & J. Ding
-
Article
| Open AccessSelf-assembly of amorphous calcium carbonate microlens arrays
Biological materials efficiently exploit self-assembly of simple constituents to produce complex functional structures such as optical devices. By controlling organic molecules, Leeet al. show fast two-step self-assembly of CaCO3microlens arrays, reminiscent of their biological counterparts.
- Kyubock Lee
- , Wolfgang Wagermaier
- & Peter Fratzl
-
Article
| Open AccessPrecise hierarchical self-assembly of multicompartment micelles
Multicompartment micelles can be assembled from block copolymers but it is difficult to manipulate their hierarchical superstructures using straightforward concepts. Here, methods are developed that involve the pre-assembly of subunits for the structurally controlled production of micelles.
- André H. Gröschel
- , Felix H. Schacher
- & Axel H.E. Müller
-
Article
| Open AccessZigzag line defects and manipulation of colloids in a nematic liquid crystal in microwrinkle grooves
Understanding defects in liquid crystals is important for controlling their structure and self-assembly properties. Here, nematic liquid crystals confined in microwrinkle grooves show new periodic arrangements and zigzag line defects that can trap particles, offering a method for colloid manipulation.
- Takuya Ohzono
- & Jun-ichi Fukuda
-
Article
| Open AccessRepeated growth and bubbling transfer of graphene with millimetre-size single-crystal grains using platinum
Grain boundaries in graphene degrade its properties, and large single-crystal graphene is desirable for electronic applications of graphene. Gaoet al. develop a method to produce millimetre-sized hexagonal single-crystal graphene grains, and films composed of the grains, on platinum by chemical vapour deposition.
- Libo Gao
- , Wencai Ren
- & Hui-Ming Cheng
-
Article
| Open AccessResolving the electromagnetic mechanism of surface-enhanced light scattering at single hot spots
Light scattering from nanoscale objects can be dramatically enhanced in the proximity of optical antennas. Here, by studying the amplitude and phase of the light scattered from a tip located at the hot spot of an antenna, the underlying electromagnetic mechanism of this enhancement is resolved.
- P. Alonso-González
- , P. Albella
- & R. Hillenbrand
-
Article |
Fully inorganic oxide-in-oxide ultraviolet nanocrystal light emitting devices
Light-emitting diodes in the form of nanocrystals offer promise for environmental and biomedical diagnostics. Brovelliet al. present a method for realizing mechanically robust and chemically stable nanocrystals emitting light in the ultraviolet range.
- Sergio Brovelli
- , Norberto Chiodini
- & Alberto Paleari
-
Article |
Wide bandgap tunability in complex transition metal oxides by site-specific substitution
Tuning the bandgap of complex transition metal oxides in a manner that preserves their intrinsic properties has so far remained elusive. Choiet al. demonstrate that the bandgap of bismuth titanate can be varied by substitutional alloying with lanthanum cobaltate, without altering its ferroelectric properties.
- Woo Seok Choi
- , Matthew F. Chisholm
- & Ho Nyung Lee
-
Article |
Emergence of non-centrosymmetric topological insulating phase in BiTeI under pressure
The spin–orbit interaction affects the electronic structure of many solids to give rise to a host of unusual phenomena. Bahramyet al.theoretically examine its role in the non-centrosymmetric compound BiTeI, and find that under the application of pressure, it leads to topologically insulating behaviour.
- M.S. Bahramy
- , B.-J. Yang
- & N. Nagaosa
-
Article
| Open AccessCMOS-based carbon nanotube pass-transistor logic integrated circuits
Field-effect transistors fabricated from carbon nanotubes have been investigated extensively over the past two decades. This study demonstrates a nanotube-based integrated circuit design that substantially improves the speed and power consumption with respect to silicon-based integrated circuits.
- Li Ding
- , Zhiyong Zhang
- & Lian-Mao Peng
-
Article |
Broadband light management using low-Q whispering gallery modes in spherical nanoshells
Control of light absorption in optical devices, such as solar cells, can be achieved through resonant features like whispering gallery modes. Here, these modes are exploited in spherical silicon nanoshells to enhance absorption over a broad spectral range in nanometre-scale flexible layers.
- Yan Yao
- , Jie Yao
- & Yi Cui
-
Article
| Open AccessSynergistic toughening of composite fibres by self-alignment of reduced graphene oxide and carbon nanotubes
Composite fibres made of polymers reinforced by carbon nanotubes are known for their exceptional toughness. Shinet al. make these composites even tougher, by self-aligning carbon nanotubes and reduced graphene oxide flakes within the polymer matrix.
- Min Kyoon Shin
- , Bommy Lee
- & Seon Jeong Kim
-
Article |
Atom-specific spin mapping and buried topological states in a homologous series of topological insulators
Strategies to tune the surface properties of topological insulators are essential, if they are to find use in applications. Using a combination of theoretical and experimental techniques, this study examines how the properties of ordered ternary topological insulators vary with the content of group IV elements.
- Sergey V. Eremeev
- , Gabriel Landolt
- & Evgueni V. Chulkov
-
Article |
Tunable Dirac cone in the topological insulator Bi2-xSbxTe3-ySey
The surface electronic structure of topological insulators is characterized by a so-called Dirac cone energy dispersion. This study shows that by tuning the compositions in the compound Bi2−xSbxTe3−ySeyone can control the precise features of its Dirac cone structure while keeping it a bulk insulator.
- T. Arakane
- , T. Sato
- & Yoichi Ando