Techniques and instrumentation

  • Article
    | Open Access

    Measuring real time magnetization dynamics resulting from Hall effects is hard due to the small signal size. Here Sala et al demonstrate a method of performing Hall resistance measurements with sub-ns resolution, and use it to investigate the switching of GdFeCo dots induced by spin-orbit torques.

    • G. Sala
    • , V. Krizakova
    •  & P. Gambardella
  • Article
    | Open Access

    Crystal defects critically influence surface chemical reactions in nanomaterials, yet the basic mechanisms at play are still elusive. Here, the authors show the atomic-scale dynamics of surface oxidation at coherent planar defects in Ag and Pd, revealing how twins and stacking-faults selectively oxidize metallic nanocrystals.

    • Qi Zhu
    • , Zhiliang Pan
    •  & Jiangwei Wang
  • Article
    | Open Access

    The charging of Fe and Mn oxide anodes in lithium-ion batteries are believed to form rocksalt phases via reconstructive conversion reactions. Here, the authors show that MxOy (M = Fe, Mn) transform into non-native body-centred cubic FeO and zincblende MnO via topotactic displacement-like pathways.

    • Xiao Hua
    • , Phoebe K. Allan
    •  & Andrew L. Goodwin
  • Article
    | Open Access

    Atomic force microscopy (AFM) provides high resolution, but is limited to small areas. Here, the authors introduce a massively parallel AFM approach with >1000 probes in a cantilever-free probe architecture, and present an optical method for detecting probe–sample contact with sub-10 nm vertical precision.

    • Wenhan Cao
    • , Nourin Alsharif
    •  & Keith A. Brown
  • Article
    | Open Access

    Magnetic reconnection and plasma turbulence occur in atmospheric and magnetized laboratory plasmas. Here the authors report evolution of magnetic islands and plasma turbulence in tokamak plasmas using high resolution 2D electron cyclotron emission diagnostics.

    • Minjun J. Choi
    • , Lāszlo Bardōczi
    •  & George McKee
  • Article
    | Open Access

    Molecular sieving typically occurs when molecules with smaller kinetic diameter than a nanopore selectively enter the pore. Here the authors show, using photoluminescence imaging and ab initio molecular dynamics simulations, that single-walled carbon nanotubes can separate n-hexane from cyclohexane, despite both having larger kinetic diameter than the nanopore.

    • Haoran Qu
    • , Archith Rayabharam
    •  & YuHuang Wang
  • Article
    | Open Access

    3D printing offers flexibility in fabrication of polymer objects but fabrication of large polymer structures with micrometer-sized geometrical features are challenging. Here, the authors introduce a method combining advantages of 3D printing and polymerization-induced phase separation, which enables formation of 3D polymer structures with controllable inherent porosity.

    • Zheqin Dong
    • , Haijun Cui
    •  & Pavel A. Levkin
  • Article
    | Open Access

    High-resolution transmission electron microscopy (HRTEM) has been transformative to the field of polymer science but most HRTEM studies are limited by beam damage on the material. Here, the authors examine the effect of the addition of antioxidants to a series of conjugated polymers and demonstrate minimized beam damage at increased resolution.

    • Brooke Kuei
    •  & Enrique D. Gomez
  • Article
    | Open Access

    Standard benchmarking of single-molecule localization microscopy cannot quantify nanoscale accuracy of arbitrary datasets. Here, the authors present Wasserstein-induced flux, a method using a chosen perturbation and knowledge of the imaging system to measure confidence of individual localizations.

    • Hesam Mazidi
    • , Tianben Ding
    •  & Matthew D. Lew
  • Article
    | Open Access

    Ferroelectric domain wall profiles can be modeled by phenomenological Ginzburg-Landau theory, with different candidate models and parameters. Here, the authors solve the problem of model selection by developing a Bayesian inference framework allowing for uncertainty quantification and apply it to atomically resolved images of walls. This analysis can also predict the level of microscope performance needed to detect specific physical phenomena.

    • Christopher T. Nelson
    • , Rama K. Vasudevan
    •  & Sergei V. Kalinin
  • Article
    | Open Access

    Single-cell immunoblotting previously separated proteins on a polyacrylamide slab in the xy direction and was limited by throughput and sample consumption. Here the authors adapt the system to separate proteins in the z direction, allowing for closer spacing of sample wells and improved sample consumption.

    • Samantha M. Grist
    • , Andoni P. Mourdoukoutas
    •  & Amy E. Herr
  • Article
    | Open Access

    To what extent the charge carriers can alter phonon heat conduction at environmental temperatures through electron–phonon interactions is an open question. Here, the authors demonstrate substantial reduction in thermal conductivity at high charge carrier densities due to significant phonon scatterings by electrons.

    • Jiawei Zhou
    • , Hyun D. Shin
    •  & Gang Chen
  • Article
    | Open Access

    Precise patterning of functional nanoparticles can provide a powerful tool for next-generation macroscale devices. Here, the authors report a reliable nanoprinting technique that can pattern various functional nanoparticles on the substrate with a 200 nm pitch and 10 nm position accuracy, and above the millimeter scale.

    • Xing Xing
    • , Zaiqin Man
    •  & Zhenda Lu
  • Article
    | Open Access

    Controlled particle acceleration in plasmas requires precise measurements of the excited wakefield. Here the authors report and demonstrate a high-resolution method to measure the effective longitudinal electric field of a beam-driven plasma-wakefield accelerator.

    • S. Schröder
    • , C. A. Lindstrøm
    •  & J. Osterhoff
  • Article
    | Open Access

    Optical atomic clocks are useful tools for frequency metrology. Here the authors explore the stability of the atomic clocks and the role of the spin squeezed states for the noise reduction in these clocks.

    • Marius Schulte
    • , Christian Lisdat
    •  & Klemens Hammerer
  • Article
    | Open Access

    Machine learning driven research holds big promise towards accelerating materials’ discovery. Here the authors demonstrate CAMEO, which integrates active learning Bayesian optimization with practical experiments execution, for the discovery of new phase- change materials using X-ray diffraction experiments.

    • A. Gilad Kusne
    • , Heshan Yu
    •  & Ichiro Takeuchi
  • Article
    | Open Access

    Shark teeth have short lifespans yet can be subject to significant mechanical damage. Here, the authors report on a site-specific damage mechanism in shark teeth enameloid, which maintains tooth functional shape, providing experimental evidence that tooth architecture may have influenced the diversification of shark ecologies over evolution.

    • Shahrouz Amini
    • , Hajar Razi
    •  & Peter Fratzl
  • Article
    | Open Access

    Mechanically interlocking dissimilar materials, such as metals and polymers, is a challenging yet promising pathway for designing and fabricating complex systems on the small scale. Here, the authors report a novel interlocking fabrication scheme and showcase the fabrication of microrobots via 3D-lithography.

    • C. C. J. Alcântara
    • , F. C. Landers
    •  & S. Pané
  • Article
    | Open Access

    Magneto-optic Kerr effect microscopy is useful for dynamic magnetic studies, but is limited by the weak magneto-optical activity. Here, the authors show that extreme anti-reflection result in a Kerr amplitude as large as 20° and enables real-time detection of sub-wavelength magnetic domain reversals.

    • Dongha Kim
    • , Young-Wan Oh
    •  & Min-Kyo Seo
  • Article
    | Open Access

    Non-line-of-sight imaging is typically limited by loss of directional information due to diffuse reflections scattering light in all directions. Here, the authors see around corners by using vertical edges and temporal response to pulsed light to obtain angular and longitudinal resolution, respectively.

    • Joshua Rapp
    • , Charles Saunders
    •  & Vivek K. Goyal
  • Article
    | Open Access

    Study of structural inhomogeneities in zeolites is important but limited by conventional techniques. Here the authors employ in situ free-electron-laser-based time-resolved coherent X-ray diffraction imaging to visualize the effect of these inhomogeneities during catalytic deoxygenation of NOx.

    • Jinback Kang
    • , Jerome Carnis
    •  & Hyunjung Kim
  • Article
    | Open Access

    Here, the authors report on an imaging method based on localized surface plasmon resonance excitation, employing gold nanodisk arrays as substrates that enable imaging of transparent dielectric particles of several sizes. They demonstrate the ability to detect and image particles smaller than the diffraction limit at 25 nm with standard bright-field imaging.

    • Nareg Ohannesian
    • , Ibrahim Misbah
    •  & Wei-Chuan Shih
  • Article
    | Open Access

    Here, the authors combine 3D printing and liquid metal filling techniques to fabricate customised probeheads for magnetic resonance experiments. They demonstrate in situ electrochemical nuclear magnetic resonance analysis, reaction monitoring with continues-flow separation and small-sample imaging.

    • Junyao Xie
    • , Xueqiu You
    •  & Zhong Chen
  • Article
    | Open Access

    The fs control of an insulator-to-metal transition down to a few nanometers and its real-time/real space observation remain a challenge. Here, the authors demonstrate a method based on ultrafast electron microscopy to provide a nm/fs resolved view of the electronic dynamics in a single VO2 nanowire.

    • Xuewen Fu
    • , Francesco Barantani
    •  & Yimei Zhu
  • Article
    | Open Access

    The authors investigate 3D-printed tips, based on controlled microstructural architectured materials, as probes for shear-mode atomic force microscopy. They demonstrate that the tailored stiffness and energy-absorbing behaviour of the material are beneficial for improving image quality.

    • Liangdong Sun
    • , Hongcheng Gu
    •  & Zhongze Gu
  • Article
    | Open Access

    The analysis of metabolites offers promises in biomarker discovery. Here the authors demonstrate the metabolomics analysis of sub-nanoliter samples using triboelectric nanogenerator inductive nanoelectrospray ionization, which they apply to exhaled breath condensate from cystic fibrosis patients and mesenchymal stromal cells.

    • Yafeng Li
    • , Marcos Bouza
    •  & Facundo M. Fernández
  • Perspective
    | Open Access

    Discovering a sustainable route to ammonia as a fertiliser and as an energy carrier is critically important, but many recent reports on the electrochemical nitrogen reduction are false positives. Here the authors uncover the emerging experimental traps and detail protocols to reliably avoid them.

    • Jaecheol Choi
    • , Bryan H. R. Suryanto
    •  & Alexandr N. Simonov
  • Article
    | Open Access

    The realization of advanced devices from metal-organic frameworks requires the preparation of uniform and crystalline thin-films of these materials. Here the authors use chemical vapor deposition to grow single-crystal frameworks that exhibit a reversible structural transition and large conductivity response.

    • F. James Claire
    • , Marina A. Solomos
    •  & Thomas J. Kempa
  • Article
    | Open Access

    Quantifying lipid and water content in tissues non-invasively is difficult, and no method exists to quantify lipids in blood non-invasively. Here the authors develop an imaging approach called shortwave infrared meso-patterned imaging (SWIR-MPI) to detect and spatially map tissue water and lipids in preclinical models.

    • Yanyu Zhao
    • , Anahita Pilvar
    •  & Darren Roblyer
  • Article
    | Open Access

    Atomic structure of alkali metal is difficult to be revealed at room temperature because of the chemical reactivity and irradiation sensitivity. Here the authors show that electron beam-induced in situ growth of alkali metals enables the investigation of atomic structure and growth kinetics at high spatiotemporal resolution.

    • Chao Liang
    • , Xun Zhang
    •  & Yi Yu
  • Article
    | Open Access

    Complexity and harsh working conditions pose limitations for fabrication of patterned materials. Here the authors report a single-step method for in situ deposition of materials that is based on semiconductor nanoparticle assisted photon-induced chemical reduction and optical trapping.

    • Yifan Chen
    • , Siu Fai Hung
    •  & Sen Yang
  • Article
    | Open Access

    Existing high-dimensional optical imaging techniques that record space and polarization cannot detect the photon’s time of arrival due to the limited speeds of electronic sensors. Here, the authors develop a single-shot ultrafast imaging modality to record light-speed high-dimensional events with picosecond resolution.

    • Jinyang Liang
    • , Peng Wang
    •  & Lihong V. Wang
  • Article
    | Open Access

    Here, the authors demonstrate a route to high resolution microendoscopy using a multicore fibre with a photonic lantern. They show that distinct multimode patterns of light can be projected from the output of the lantern by individually exciting the single-mode MCF cores, whose patterns are highly stable to fibre movement.

    • Debaditya Choudhury
    • , Duncan K. McNicholl
    •  & Robert R. Thomson
  • Article
    | Open Access

    Urease is a nickel enzyme responsible for catalyzing the conversion of urea into ammonia and carbon dioxide. Here the authors report a high resolution cryo-EM structure of urease from the bacterial pathogen Yersinia enterocolitica, providing a detailed visualization of the urease bimetal active site and a basis for drug development.

    • Ricardo D. Righetto
    • , Leonie Anton
    •  & Henning Stahlberg
  • Article
    | Open Access

    Three-dimensional imaging of the fetal heart and quantification of blood flow in the surrounding vessels is very challenging because the heart is small and the fetus is free to move in the womb. Here, the authors demonstrate motion-corrected 4D flow MRI of the whole fetal heart and major vessels.

    • Thomas A. Roberts
    • , Joshua F. P. van Amerom
    •  & Joseph V. Hajnal
  • Article
    | Open Access

    Additive manufacturing promises a major transformation of the production of high economic value metallic materials. Here, the authors describe a new class of 3D printable superalloys that are amenable to crack-free 3D printing via electron beam melting as well as selective laser melting.

    • Sean P. Murray
    • , Kira M. Pusch
    •  & Tresa M. Pollock
  • Article
    | Open Access

    Interfacial fluctuations at the nanoscale, such as shape evolution of a growing crystal, are prohibitively difficult to study experimentally. Here, the authors are able to map the kinetic and thermodynamic parameters involved in shaping of nanoparticle supracrystals by directly imaging the fluctuating crystal surface by liquid-phase TEM, and analyzing it in the context of capillary wave theory.

    • Zihao Ou
    • , Lehan Yao
    •  & Qian Chen
  • Article
    | Open Access

    The delithiation process in lithium excess cathode material of Li2MnO3 has remained unclear. Here, the authors report that delithiation is governed by the climb motion of dislocations with the aid of oxygen-release, determined directly by atomic-resolution STEM imaging and spectroscopy.

    • Kei Nakayama
    • , Ryo Ishikawa
    •  & Yuichi Ikuhara
  • Perspective
    | Open Access

    Despite their widespread use, many fundamental questions about the internal structure of microgels are still open. Here the authors describe several pathways toward a complete understanding of microgel colloids based on recent experimental advances in nanoscale characterization.

    • Frank Scheffold
  • Article
    | Open Access

    Single-molecule sensing is very challenging due to weak emitted signals and environmental interference. Here the authors design a method (i-SET) for single molecule sensing with core-shell upconverting nanoparticles, which relies on signal enhancement by the activator-rich probes to quantify fluorophores attached to a single nanoparticle.

    • Jian Zhou
    • , Changyu Li
    •  & Renren Deng