Physics

  • Article
    | Open Access

    The experimental realization of higher order topological insulator (HOTI) in solid state materials remains elusive. Here, Aggarwal et al. reveal hinge states on three edges of both Bi and Bi0.92Sb0.08 (110) islands, supporting them as a class of HOTI.

    • Leena Aggarwal
    • , Penghao Zhu
    •  & Vidya Madhavan
  • Article
    | Open Access

    Several key tasks in quantum information processing can be regarded as channel manipulation. Here, focusing on the class of distillation protocols, the authors derive general bounds on resource overhead and incurred errors, showing application to magic state distillation and quantum channel capacities.

    • Bartosz Regula
    •  & Ryuji Takagi
  • Article
    | Open Access

    Nuclear spins in diamond are promising for applications in quantum technologies due to their long coherence times. Here, the authors demonstrate a scalable electrical readout of individual intrinsic 14N nuclear spins in diamond, mediated by hyperfine coupling to electron spin of the NV center, as a step towards room-temperature nanoscale diamond quantum devices.

    • Michal Gulka
    • , Daniel Wirtitsch
    •  & Milos Nesladek
  • Article
    | Open Access

    Photonics-based radars offer intriguing potential but face tradeoffs in tunability, complexity, and noise. Here the authors present microwave generation in a photonics platform by heterodyning of two low-noise, self-injection-locked lasers, and demonstrate its advantages in an FMCW radar system.

    • Eric A. Kittlaus
    • , Danny Eliyahu
    •  & Siamak Forouhar
  • Article
    | Open Access

    Photon echo techniques are difficult to implement in the quantum regime due to coherent and spontaneous emission noise. Here, the authors propose a low-noise photon-echo quantum memory approach based on all-optical control in a four-level system, and demonstrate it using a Eu3+:Y2SiO5 crystal.

    • You-Zhi Ma
    • , Ming Jin
    •  & Guang-Can Guo
  • Article
    | Open Access

    Thermoelectric effects are limited to electrons to occur, and disappear at low temperatures due to electronic entropy quenching. Here, the authors report thermoelectric generation caused by nuclear spins down to 100 mK due to nuclear-spin excitation in a magnetically ordered material MnCO3.

    • T. Kikkawa
    • , D. Reitz
    •  & E. Saitoh
  • Article
    | Open Access

    Photon upconversion with near-infrared excitation and ultraviolet emission has many applications, but suffers from low quantum efficiency. Here, the authors report a six-photon upconversion process in nanoparticles with heterogeneous core-multishell structure, that regulate the energy transfer pathway.

    • Qianqian Su
    • , Han-Lin Wei
    •  & Dayong Jin
  • Article
    | Open Access

    Photomutiplication-type organic photodetectors (PM-OPDs) are attractive for various next-generation technologies due to their lower cost, higher sensitivity and technological utility. Here, the authors report vacuum-processed narrowband PM-OPDs with enhanced sub-bandgap external quantum efficiency.

    • Jonas Kublitski
    • , Axel Fischer
    •  & Karl Leo
  • Article
    | Open Access

    Refraction between anisotropic media is still an unexplored phenomenon. Here, the authors investigate the propagation of hyperbolic phonon polaritons traversing α-MoO3 nanoprisms, showing a bending-free refraction effect and sub-diffractional focusing with foci size as small as 1/50 of the light wavelength in free space.

    • J. Duan
    • , G. Álvarez-Pérez
    •  & P. Alonso-González
  • Article
    | Open Access

    Magnetic Weyl semimetals in the 2D limit may behave like 2D Chern insulators and host the quantum anomalous Hall effect at high temperatures. Here, the authors report the observation of linearly dispersing topological states confined to the edges of the kagome Co3Sn terraces in the magnetic Weyl system Co3Sn2S2.

    • Sean Howard
    • , Lin Jiao
    •  & Vidya Madhavan
  • Article
    | Open Access

    Up-conversion photoluminescence in colloidal quantum dots is generally believed to be mediated by thermal activation from defect states. Here, the authors reveal that highly-efficient up-conversion photoluminescence instead is related to electron-phonon coupling.

    • Zikang Ye
    • , Xing Lin
    •  & Xiaogang Peng
  • Article
    | Open Access

    In real materials, a spin quantum number assumes a fixed value, which makes it challenging to realize a crossover between quantum and classical spin regimes. Here the authors demonstrate such a crossover in a weakly coupled chain compound by controlling the amount of quantum correlations, in the form of the inverse spin quantum number, with external pressure.

    • Daisuke Yamamoto
    • , Takahiro Sakurai
    •  & Yoshiya Uwatoko
  • Article
    | Open Access

    It was suggested that the breakdown of the quantum Hall effect in graphene originates from the coupling between counter propagating edge modes. Here, by using scanning gate microscopy, the authors propose a microscopic mechanism of this coupling due to antidots present at graphene edges.

    • N. Moreau
    • , B. Brun
    •  & B. Hackens
  • Article
    | Open Access

    Laser-assisted electron scattering (LAES) is a commonly observed strong field process in gas phase systems. Here the authors use helium droplets with core atoms and molecules to observe increased electron energy due to multiple LAES events within the droplets.

    • Leonhard Treiber
    • , Bernhard Thaler
    •  & Markus Koch
  • Article
    | Open Access

    The Jahn-Teller effect is the spontaneous symmetry breaking of the molecular structure caused by the coupling of electrons and nuclei. Here the authors use ultrafast Coulomb explosion imaging to map the evolution of the fundamental symmetry lowering process in photoionized methane within around 20fs.

    • Min Li
    • , Ming Zhang
    •  & Peixiang Lu
  • Article
    | Open Access

    The observation of negative capacitance effect is focused on the ferroelectrics, while the antiferroelectrics based on Landau switches may have negative capacitance effect. Here, the authors report the static and transient negative capacitance effect in antiferroelectric PbZrO3 and reveal its origin.

    • Leilei Qiao
    • , Cheng Song
    •  & Feng Pan
  • Article
    | Open Access

    Single atom magnets on surfaces offer potentially long lived and stable spin states, particular lanthanides, which can be adsorbed onto Magnesium Oxide. Here, the authors report on Dysprosium adsorbed onto Magnesium Oxide, which exhibits large magnetic anisotropy energy, and a spin life time of several days at low temperatures

    • A. Singha
    • , P. Willke
    •  & T. Choi
  • Article
    | Open Access

    Twist-angle disorder is considered a major source of sample-to-sample variation in magic-angle twisted bilayer graphene. By using scanning tunnelling spectroscopy, the authors demonstrate that a small doping inhomogeneity, present in typical samples, is amplified near the flat band edges and can be another source of disturbance for the flat band physics.

    • Nikhil Tilak
    • , Xinyuan Lai
    •  & Eva Y. Andrei
  • Article
    | Open Access

    Strong nonlinearities, like high harmonic generation in optical systems, can lead to interesting applications in photonics. Here the authors fabricate a thin resonant gallium phosphide metasurface capable of avoiding the laser-induced damage and demonstrate efficient even and odd high harmonic generation from it when driven by mid-infrared laser pulses.

    • Maxim R. Shcherbakov
    • , Haizhong Zhang
    •  & Gennady Shvets
  • Article
    | Open Access

    The Doppler effect is a wave phenomenon that can find the magnitude of velocity of moving targets with scalar waves. Here, the authors use vectorially structured light with spatially variant polarization to fully determine both the magnitude of velocity and motion direction of a moving particle.

    • Liang Fang
    • , Zhenyu Wan
    •  & Jian Wang
  • Article
    | Open Access

    Hybrid devices based on electrons on helium may find application in quantum devices. Here the authors demonstrate surface acoustic wave driven acoustoelectric transport of electrons on superfluid helium.

    • H. Byeon
    • , K. Nasyedkin
    •  & J. Pollanen
  • Article
    | Open Access

    Despite the discovery of Majorana zero modes (MZM) in iron-based superconductors, sample inhomogeneity may destroy MZMs during braiding. Here, authors observe MZM in impurity-assisted vortices due to tuning of the bulk Dirac fermions in a homogeneous superconductor LiFeAs.

    • Lingyuan Kong
    • , Lu Cao
    •  & Hong Ding
  • Article
    | Open Access

    Long-range coherent spin-qubit transfer between semiconductor quantum dots requires understanding and control over associated errors. Here, the authors achieve high-fidelity coherent state transfer in a Si double quantum dot, underpinning the prospects of a large-scale quantum computer.

    • J. Yoneda
    • , W. Huang
    •  & A. S. Dzurak
  • Article
    | Open Access

    Cells can modify their environment by depositing biochemical signals or mechanically remodelling the extracellular matrix; the impact of such self-induced environmental perturbations on cell trajectories at various scales remains unexplored. Here authors show that motile cells leave long-lived physicochemical footprints along their way, which determine their future path.

    • Joseph d’Alessandro
    • , Alex Barbier--Chebbah
    •  & Benoît Ladoux
  • Article
    | Open Access

    Estimating velocities in gas liquid flows is of importance in many engineering applications. Hohermuth et al. show that previous bubble velocities obtained from intrusive probes have been underestimated and provide a correction scheme for more accurate velocity measurements.

    • B. Hohermuth
    • , M. Kramer
    •  & D. Valero
  • Article
    | Open Access

    Reactions at the interface between mineral surfaces and flowing liquids are ubiquitous in nature. Here the authors explore, using surface-specific sum frequency generation spectroscopy and numeric calculations, how the liquid flow affects the charging and dissolution rates leading to flow-dependent charge gradients along the surface.

    • Patrick Ober
    • , Willem Q. Boon
    •  & Mischa Bonn
  • Article
    | Open Access

    Interatomic Coulombic decay, ICD, is commonly observed in systems weakly bound to different environments. Here the authors discuss the ICD in an electromagnetic cavity and show that the entanglement of atoms can change ICD rates substantially and be used to control the ICD process.

    • Lorenz S. Cederbaum
    •  & Alexander I. Kuleff
  • Article
    | Open Access

    Mechanisms of cluster formation in networks with directed links differ from those in undirected networks. Lodi et al. propose a method to compute interdependencies among clusters of nodes in directed networks. They show that clusters can be one-way dependent, as found in social and neural networks.

    • Matteo Lodi
    • , Francesco Sorrentino
    •  & Marco Storace
  • Article
    | Open Access

    Nuclear spin polarization and relaxation can be studied using nuclear magnetic resonance (NMR). Here the authors demonstrate a combination of fast-field cycling and optical magnetometry techniques, to realize a NMR sensor that operates in the region of very low frequency and high relaxation rate.

    • Sven Bodenstedt
    • , Morgan W. Mitchell
    •  & Michael C. D. Tayler
  • Article
    | Open Access

    Normally the diffusionless solid-to-solid transition between phases are driven by athermal processes, due to strain being overwhelmingly dominant. Here, the authors present a unique series of in-situ particle level observations of the solid-to-solid transition in colloidal particles suspended in a solvent, revealing new transition pathways.

    • Minhuan Li
    • , Zhengyuan Yue
    •  & Peng Tan
  • Article
    | Open Access

    Neuromorphic nanowire networks are found to exhibit neural-like dynamics, including phase transitions and avalanche criticality. Hochstetter and Kuncic et al. show that the dynamical state at the edge-of-chaos is optimal for learning and favours computationally complex information processing tasks.

    • Joel Hochstetter
    • , Ruomin Zhu
    •  & Zdenka Kuncic
  • Article
    | Open Access

    The nature of spin interactions and the field-induced quantum spin liquid phase in the Kitaev material α-RuCl3 have been debated. Here, using a combination of many-body techniques, the authors derive an effective spin model that explains the majority of experimental findings and predicts a new quantum spin liquid phase in strong out-of-plane magnetic field.

    • Han Li
    • , Hao-Kai Zhang
    •  & Wei Li
  • Article
    | Open Access

    Dissipative solitons and their symmetry breaking is important for photonic applications. Here the authors show that dissipative solitons can undergo spontaneous symmetry breaking in a two-component nonlinear optical ring resonator, resulting in the coexistence of distinct vectorial solitons with asymmetric, mirror-like states of polarization.

    • Gang Xu
    • , Alexander U. Nielsen
    •  & Miro Erkintalo
  • Article
    | Open Access

    Although N-heterocyclic carbenes (NHCs) are a promising class of ligands for forming robust self-assembled monolayers on metals, many questions remain about their behavior on surfaces. Here, the authors address these fundamental questions—such as the factors controlling NHC orientation, mobility, and ability to self-assemble—through an in-depth examination of NHC overlayers on Au(111).

    • Alex Inayeh
    • , Ryan R. K. Groome
    •  & Alastair B. McLean
  • Article
    | Open Access

    Recent advances in the identification and growth of antiferromagnetic topological insulators open the way to the manipulation of the chiral edge states that are topologically required at their step edges and domain walls. Here, the authors propose a quantum point junction formed by two types of edge states and discuss its applications in electron quantum optics.

    • Nicodemos Varnava
    • , Justin H. Wilson
    •  & David Vanderbilt
  • Article
    | Open Access

    In all experimentally observed Weyl semimetals so far, the Weyl points always appear in pairs in the momentum space. Here, the authors report one unpaired Weyl point without surface Fermi arc emerging at the center of the Brillouin zone, which is surrounded by charged Weyl nodal walls in PtGa.

    • J.-Z. Ma
    • , Q.-S. Wu
    •  & M. Shi
  • Article
    | Open Access

    The authors present a microwave imaging system that can operate in continuous transmit-receive mode. Using an array of transmitters, a single receiver and a reconstruction matrix that correlate random time patterns with the captured signal, they demonstrate real-time imaging and tracking through a wall.

    • Fabio C. S. da Silva
    • , Anthony B. Kos
    •  & Archita Hati
  • Article
    | Open Access

    Controlled actuation is an important aspect of synthetic cellular systems. Here, the authors combine pH responsive DNA origami structures with light triggered proton pump engineered E. coli to trigger a change in pH and control the deformation of giant unilamellar vesicles by simple illumination.

    • Kevin Jahnke
    • , Noah Ritzmann
    •  & Kerstin Göpfrich
  • Article
    | Open Access

    Conductive domain walls have been usually found in ferroelectric oxides. Here, the authors report on giant conductivity of domain walls and their magnetically avalanche-like expulsion event in non-oxide ferroelectric GaV4S8, extending the source of phenomena beyond the realm of oxide electronics.

    • S. Ghara
    • , K. Geirhos
    •  & I. Kézsmárki
  • Article
    | Open Access

    Two possible scenarios of the superconducting order parameter in Sr2RuO4 remain difficult to distinguish. Here, the authors observe that the onset temperature of time reversal symmetry breaking tracks the superconducting transition temperature in Sr2RuO4, supporting a dxz ± idyz order parameter.

    • Vadim Grinenko
    • , Debarchan Das
    •  & Rustem Khasanov
  • Article
    | Open Access

    It was suggested that some 3d materials display bond-dependent exchange interactions, leading to exotic many-body effects. Here, using inelastic neutron scattering, the authors reveal such interactions in the stacked honeycomb magnet CoTiO3 and show how they induce a spectral gap and affect the Dirac magnon band structure.

    • M. Elliot
    • , P. A. McClarty
    •  & R. Coldea
  • Article
    | Open Access

    Magnetized plasma can be regarded as topological matter. Here the authors identify a necessary and sufficient condition for the existence of topological edge mode and find that cold magnetized plasma has ten topological phases in the plasma frequency, cyclotron frequency and wave-vector space.

    • Yichen Fu
    •  & Hong Qin
  • Article
    | Open Access

    Developing new methods for structuring light’s chirality in space would be advantageous for various next-generation applications. Here, the authors report enantio-sensitive unidirectional light bending by interacting light with isotropic chiral media.

    • David Ayuso
    • , Andres F. Ordonez
    •  & Olga Smirnova