A5088867481- Electron and X-Ray Spectroscopy Techniques
- Advanced Electron Microscopy Techniques and Applications
- Semiconductor materials and devices
- Semiconductor materials and interfaces
- Integrated Circuits and Semiconductor Failure Analysis
- Surface and Thin Film Phenomena
- Plasmonic and Surface Plasmon Research
- Silicon Nanostructures and Photoluminescence
- Electronic and Structural Properties of Oxides
- Gold and Silver Nanoparticles Synthesis and Applications
- Near-Field Optical Microscopy
- Nanowire Synthesis and Applications
- Ion-surface interactions and analysis
- Silicon and Solar Cell Technologies
- Advanced Materials Characterization Techniques
- Force Microscopy Techniques and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- Physics of Superconductivity and Magnetism
- Diamond and Carbon-based Materials Research
- Quantum Dots Synthesis And Properties
- Electrocatalysts for Energy Conversion
- Advancements in Semiconductor Devices and Circuit Design
- Intermetallics and Advanced Alloy Properties
- Thin-Film Transistor Technologies
- Atomic and Molecular Physics
Rutgers, The State University of New Jersey
2015-2024
Rutgers Sexual and Reproductive Health and Rights
2011-2023
Advanced Materials and Devices (United States)
2015-2019
Materials Science & Engineering
1977-2011
Donostia International Physics Center
2010
Foundation for Research and Technology Hellas
2010
IBM Research - Thomas J. Watson Research Center
1994-2009
IBM (United States)
1996-2008
Cornell University
1980-2008
University of Glasgow
1978-1979
An inelastic scattering process is observed between 2.5 and 4.0 eV when clusters of 10- to 50-nm-diam aluminum spheres are excited by a 1-nm-diam probe 100-keV electrons. This maximum the incident electron positioned within 10 nm smaller two touching spheres. The energy spatial variation probability consistent with calculation for two-sphere system immersed in oxide.
Single atom catalysts provide exceptional activity. However, measuring the intrinsic catalytic activity of a single in real electrochemical environments is challenging. Here, we report vacancy for electrocatalytically evolving hydrogen two-dimensional (2D) MoS2. Surprisingly, find that per not constant but increases with its concentration, reaching sudden peak at 5.7 × 1014 cm–2 where turn over frequency and Tafel slope atomic was found to be ∼5 s–1 44 mV/dec, respectively. At this also...
Nondestructive neurotransmitter detection and real-time monitoring of stem cell differentiation are both great significance in the field neurodegenerative disease regenerative medicine. Although luminescent biosensing nanoprobes have been developed to address this need, they intrinsic limitations such as autofluorescence, scattering, phototoxicity. Upconversion nanoparticles (UCNPs) gained increasing attention for various biomedical applications due their high photostability, low...
Liquid-phase chemical exfoliation can achieve industry-scale production of two-dimensional (2D) materials for a wide range applications. However, many 2D with potential applications in quantum technologies often fail to leave the laboratory setting because their air sensitivity and depreciation physical performance after processing. We report simple method create stable, aqueous, surfactant-free, superconducting ink containing phase-pure 1T'-WS2 monolayers that are isostructural...
H2 production by direct photoelectrochemical (PEC) water splitting has remained unachievable commercially, mainly due to rapid failure at the interface between photoabsorber(s) and catalyst(s). PEC devices made from multijunction III–V semiconductors with platinum group metal (PGM) catalysts have yielded impressive initial solar-to-H2 (STH) efficiency >19%, which rapidly corrodes in aqueous electrolytes. Here, TiO2/TiN layers were fused create a bifunctional GaInP2/GaAs tandem photoabsorber...
We describe highly accurate (0.2-1%) intensity measurements for the inelastic scattering of 75-keV electrons in \ensuremath{\sim} 1000-\AA{}-thick polycrystalline aluminum films region (0.0-3.1)-${\mathrm{\AA{}}}^{\ensuremath{-}1}$ transferred wave vector and (0-100)-eV energy loss. The work was performed on Cornell University electron spectrometer-microscope-computer system. These clarify some experimental problems associated with multiple which obscure single distribution. present a new...
An electron beam can drill nanopores in SiO2 or silicon nitride membranes and shrink a pore to smaller diameter. Such are promising for single molecule detection. The formation 40nm thick nitride∕SiO2 bilayer using an with diameter of 8nm (full width half height) was investigated by energy loss spectroscopy facing toward away from the source. O shows almost linear—independent which layer faces source, while N is quite complicated. After pore, membrane presents wedge shape over 70nm radius...
A Wien Filter electron spectrometer has been successfully combined with a dedicated scanning transmission microscope (STEM) to obtain an energy resolution of 140 meV specimen collection semiangle 25 mR at 100 keV. cold-field emission source is used produce 0.35–10-nm-size beam which spread in about 0.25 eV. Because this much larger than the resolution, deconvolution techniques may be applied under appropriate conditions yield spectroscopic 70 12.5-mR semiangle. The conventional design, but...
Manipulation of nanoscale objects to build useful structures requires a detailed understanding and control forces that guide motion. We report here observation electromagnetic in groups metal particles, derived from the plasmonic response passage swift electron beam. At moderate impact parameters, are attractive, toward beam, agreement with simple image charge arguments. For smaller however, repulsive, driving nanoparticle away passing electron. Particle pairs most often pulled together by...
We measure phonon energy gain and loss down to 20 meV in a single nanostructure using an atom-wide monochromatic electron beam. show that the bulk surface, processes obey principle of detailed balancing nanostructured systems at thermal equilibrium. By plotting logarithm ratio bulk/surface scattering as function excitation energy, we find linear behavior, expected from balance arguments. Since universal linearity scales with inverse nanosystem temperature only, can probed object precision...
The characteristic excitation of a metal is its plasmon, which quantized collective oscillation electron density. In 1956, David Pines predicted that distinct type dubbed 'demon', could exist in three-dimensional (3D) metals containing more than one species charge carrier1. Consisting out-of-phase movement electrons different bands, demons are acoustic, electrically neutral and do not couple to light, so have never been detected an equilibrium, 3D metal. Nevertheless, believed be critical...
Spatially resolved electron energy loss spectroscopy has been performed on single, H-terminated, Si nanocrystals in the size range 25--500 \AA{}. The particles were prepared via gas-phase photolysis of a dilute ${\mathrm{Si}}_{2}$${\mathrm{H}}_{6}$/He mixture gas flow cell, and deposited holey carbon grid for analysis. Energy within few eV core 2p ionization edge reveals information about conduction band states at ${\mathrm{\ensuremath{\Delta}}}_{1}$ ${\mathit{L}}_{1}$ Brillouin zone. is...
Solid-state nanopores fabricated by a high-intensity electron beam in ceramic membranes can be fine-tuned on three-dimensional geometry and composition choice of materials sculpting conditions. For similar conditions, 8 nm diameter containing SiO(2) show large depletion areas (70 radius) with small sidewall angles (55 degrees ), whereas those made SiN (40 nm) larger (75 ). Three-dimensional tomograms SiO(2)/SiN/SiO(2) membrane biconical shape symmetric top bottom indicate mixing layers up to...
The authors have examined the role of sub nanometer La2O3 and LaN cap layers interposed in Si∕HfO2∕TiN high-k gate dielectric stacks tuning flatband threshold voltages capacitors transistors. High performance, band edge n metal oxide field effect transistors with channel lengths down to 60nm may be fabricated without significant compromise mobility, electrical thickness, voltage. They carried out a microstructural evaluation these correlated results behavior devices.
The reactions of Pd on atomically clean or air-exposed (100) and (110) GaAs surfaces at temperatures between 20 to 500 °C in different ambients were investigated by transmission electron microscopy. Interfacial quite from previous x-ray results observed two new Pd-Ga-As ternary phases identified for the first time. At lower (T≲250 °C) formation a phase PdGa∼0.3As∼0.2, which has hexagonal structure very similar that Pd2Ge Pd2Si with a0=b0=0.672 nm c0=0.340 nm, was observed. This is...
The movement of heavy atoms on a thin carbon substrate is readily observed using sub-Angstrom electron probe. consistent with an beam activation mechanism whereby are occasionally detached from bonding sites, allowing rapid diffusion to new sites that may be quite far the original. most often lie at defects, steps, and other asperities in substrate. Formation three-dimensional clusters can occur during several isolated atoms. Coalescence dissolution larger islands both under varying...
Electron-energy-loss spectroscopy was used to study the quantum size effect in surface-plasmon excitations of small metallic particles, with diameters ranging from 4 20 nm. Scanning transmission electron microscopy used, which provided capability observing electron-energy-loss spectra individual, well-characterized silver particles. The measured relation between energy and particle shows a definite deviation that predicted by macroscopic theories, cannot be well explained existing...
Abstract The structure of the epitaxial Pd2Si/(111)Si interface has been investigated by transmission electron microscopy. Observations normal to using weak-beam technique demonstrate presence misfit dislocations and support a model where atomically smooth regions are coherent associated with interfacial steps. High-resolution lattice images (110) cross-sectional specimens consistent this model, showing characteristic image features which may be explained theoretical multislice simulations....