Graphene binding on black phosphorus enables high on/off ratios and mobility.

Graphene is one of the most promising candidates for integrated circuits due to its robustness against short-channel effects, inherent high carrier mobility and desired gapless nature for Ohmic contact, but it is difficult to achieve satisfactory on/off ratios even at the expense of its carrier mobility, limiting its device applications. Here, we present a strategy to realize high back-gate switching ratios in a graphene monolayer with well-maintained high mobility by forming a vertical heterostructure with a black phosphorus multi-layer. By local current annealing, strain is introduced within an established area of the graphene, which forms a reflective interface with the rest of the strain-free area and thus generates a robust off-state via local current depletion.

Temperature-Dependent Coherent Tunneling across Graphene-Ferritin Biomolecular Junctions.

Understanding the mechanisms of charge transport (CT) across biomolecules in solid-state devices is imperative to realize biomolecular electronic devices in a predictive manner. Although it is well-accepted that biomolecule-electrode interactions play an essential role, it is often overlooked. This paper reveals the prominent role of graphene interfaces with Fe-storing proteins in the net CT across their tunnel junctions.

Modulation of Spin Dynamics in 2D Transition-Metal Dichalcogenide via Strain-Driven Symmetry Breaking.

Transition metal dichalcogenides (TMDs) possess intrinsic spin-orbit interaction (SOI) with high potential to be exploited for various quantum phenomena. SOI allows the manipulation of spin degree of freedom by controlling the carrier's orbital motion via mechanical strain. Here, strain modulated spin dynamics in bilayer MoS field-effect transistors (FETs) fabricated on crested substrates are demonstrated.

Biomolecular control over local gating in bilayer graphene induced by ferritin.

Electrical field-induced charge modulation in graphene-based devices at the nanoscale with ultrahigh density carrier accumulation is important for various practical applications. In bilayer graphene (BLG), inversion symmetry can simply be broken by an external electric field. However, control over charge carrier density at the nanometer scale is a challenging task.

Influence of Sr deficiency on structural and electrical properties of SrTiO thin films grown by metal-organic vapor phase epitaxy.

Homoepitaxial growth of SrTiO thin films on 0.5 wt% niobium doped SrTiO (100) substrates with high structural perfection was developed using liquid-delivery spin metal-organic vapor phase epitaxy (MOVPE). Exploiting the advantage of adjusting the partial pressures of the individual constituents independently, we tuned the Sr/Ti ratio of the gas phase for realizing, stoichiometric, as well as Sr deficient layers.

Imprinting Ferromagnetism and Superconductivity in Single Atomic Layers of Molecular Superlattices.

Ferromagnetism and superconductivity are two antagonistic phenomena since ferromagnetic exchange fields tend to destroy singlet Cooper pairs. Reconciliation of these two competing phases has been achieved in vertically stacked heterostructures where these two orders are confined in different layers. However, controllable integration of these two phases in one atomic layer is a longstanding challenge.

Charge disproportionate molecular redox for discrete memristive and memcapacitive switching.

Electronic symmetry breaking by charge disproportionation results in multifaceted changes in the electronic, magnetic and optical properties of a material, triggering ferroelectricity, metal/insulator transition and colossal magnetoresistance. Yet, charge disproportionation lacks technological relevance because it occurs only under specific physical conditions of high or low temperature or high pressure. Here we demonstrate a voltage-triggered charge disproportionation in thin molecular films of a metal-organic complex occurring in ambient conditions.

Gate controlled valley polarizer in bilayer graphene.

Sign reversal of Berry curvature across two oppositely gated regions in bilayer graphene can give rise to counter-propagating 1D channels with opposite valley indices. Considering spin and sub-lattice degeneracy, there are four quantized conduction channels in each direction. Previous experimental work on gate-controlled valley polarizer achieved good contrast only in the presence of an external magnetic field.

Polarity Tunable Trionic Electroluminescence in Monolayer WSe.

Monolayer WSe exhibits luminescence arising from various types of exciton complexes due to strong many-body effects. Here, we demonstrate selective electrical excitation of positive and negative trions in van der Waals metal-insulator-semiconductor (MIS) heterostructure consisting of few-layer graphene (FLG), hexagonal boron nitride (hBN), and monolayer WSe. Intentional unbalanced injection of electrons and holes is achieved via field-emission tunneling and electrostatic accumulation.

Crested two-dimensional transistors.

Two-dimensional transition metal dichalcogenide (TMD) materials, albeit promising candidates for applications in electronics and optoelectronics, are still limited by their low electrical mobility under ambient conditions. Efforts to improve device performance through a variety of routes, such as modification of contact metals and gate dielectrics or encapsulation in hexagonal boron nitride, have yielded limited success at room temperature. Here, we report a large increase in the performance of TMD field-effect transistors operating under ambient conditions, achieved by engineering the substrate's surface morphology.

Anatase TiO-A Model System for Large Polaron Transport.

Large polarons have been of significant recent technological interest as they screen and protect electrons from point-scattering centers. Anatase TiO is a model system for studying large polarons as they can be studied systematically over a wide range of temperature and carrier density. The electronic and magneto transport properties of reduced anatase TiO epitaxial thin films are analyzed considering various polaronic effects.

Investigating the Role of Copper Oxide in Electrochemical CO Reduction in Real Time.

Copper oxides have been of considerable interest as electrocatalysts for CO reduction (CO2R) in aqueous electrolytes. However, their role as an active catalyst in reducing the required overpotential and improving the selectivity of reaction compared with that of polycrystalline copper remains controversial. Here, we introduce the use of selected-ion flow tube mass spectrometry, in concert with chronopotentiometry, in situ Raman spectroscopy, and computational modeling, to investigate CO2R on CuO nanoneedles, CuO nanocrystals, and CuO nanoparticles.

Corrigendum: Robust resistive memory devices using solution-processable metal-coordinated azo aromatics.

This corrects the article DOI: 10.1038/nmat5009.

Robust resistive memory devices using solution-processable metal-coordinated azo aromatics.

Non-volatile memories will play a decisive role in the next generation of digital technology. Flash memories are currently the key player in the field, yet they fail to meet the commercial demands of scalability and endurance. Resistive memory devices, and in particular memories based on low-cost, solution-processable and chemically tunable organic materials, are promising alternatives explored by the industry.

Controlled Growth of 1D MoSe Nanoribbons with Spatially Modulated Edge States.

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) possess interesting one-dimensional (1D) properties at its edges and inversion domain boundaries, where properties markedly different from the 2D basal plane, such as 1D metallicity and charge density waves, can be observed. Although 2D TMDCs crystals are widely grown by chemical vapor deposition (CVD), the fabrication of 1D TMDCs ribbons is challenging due to the difficulty to confine growth in only one dimension. Here we report the controlled growth of MoSe nanoribbons with an aspect ratio >100 by using prepatterned Se reconstructions on Au(100).

Topological properties determined by atomic buckling in self-assembled ultrathin Bi(110).

Topological insulators (TIs) are a new type of electronic materials in which the nontrivial insulating bulk band topology governs conducting boundary states with embedded spin-momentum locking. Such edge states are more robust in a two-dimensional (2D) TI against scattering by nonmagnetic impurities than in its three-dimensional (3D) variant, because in 2D the two helical edge states are protected from the only possible backscattering. This makes the 2D TI family a better candidate for coherent spin transport and related applications.

Transport properties of monolayer MoS2 grown by chemical vapor deposition.

Recent success in the growth of monolayer MoS2 via chemical vapor deposition (CVD) has opened up prospects for the implementation of these materials into thin film electronic and optoelectronic devices. Here, we investigate the electronic transport properties of individual crystallites of high quality CVD-grown monolayer MoS2. The devices show low temperature mobilities up to 500 cm(2) V(-1) s(-1) and a clear signature of metallic conduction at high doping densities.

Self-aligned nanoscale SQUID on a tip.

A nanometer-sized superconducting quantum interference device (nanoSQUID) is fabricated on the apex of a sharp quartz tip and integrated into a scanning SQUID microscope. A simple self-aligned fabrication method results in nanoSQUIDs with diameters down to 100 nm with no lithographic processing. An aluminum nanoSQUID with an effective area of 0.

Informatics in radiology (infoRAD): an open source framework for modification and communication of DICOM objects.

A configurable framework has been developed that can receive, modify, and export images in different picture archiving and communication system scenarios. The framework has three main components: a receiver for Digital Imaging and Communications in Medicine (DICOM) objects, a processing pipeline to apply one or more modifications to these objects, and one or more senders to send the processed objects to predefined addresses. The toolbox programming was implemented as an open source project in Java.

DICOM router: an open source toolbox for communication and correction of DICOM objects.

Rationale And Objective: Today, the exchange of medical images and clinical information is well defined by the digital imaging and communications in medicine (DICOM) and Health Level Seven (ie, HL7) standards. The interoperability among information systems is specified by the integration profiles of IHE (Integrating the Healthcare Enterprise). However, older imaging modalities frequently do not correctly support these interfaces and integration profiles, and some use cases are not yet specified by IHE.

Localization of fractionally charged quasi-particles.

An outstanding question pertaining to the microscopic properties of the fractional quantum Hall effect is understanding the nature of the particles that participate in the localization but that do not contribute to electronic transport. By using a scanning single electron transistor, we imaged the individual localized states in the fractional quantum Hall regime and determined the charge of the localizing particles. Highlighting the symmetry between filling factors 1/3 and 2/3, our measurements show that quasi-particles with fractional charge e* = e/3 localize in space to submicrometer dimensions, where e is the electron charge.