A5072602254- Surface and Thin Film Phenomena
- Optical Coatings and Gratings
- Theoretical and Computational Physics
- Copper Interconnects and Reliability
- Magnetic properties of thin films
- Semiconductor materials and devices
- 2D Materials and Applications
- nanoparticles nucleation surface interactions
- Quantum Dots Synthesis And Properties
- Metal and Thin Film Mechanics
- Chalcogenide Semiconductor Thin Films
- Electron and X-Ray Spectroscopy Techniques
- Advanced Chemical Physics Studies
- Graphene research and applications
- Perovskite Materials and Applications
- ZnO doping and properties
- Semiconductor materials and interfaces
- Physics of Superconductivity and Magnetism
- Advanced Semiconductor Detectors and Materials
- Fluid Dynamics and Thin Films
- MXene and MAX Phase Materials
- Force Microscopy Techniques and Applications
- Photonic and Optical Devices
- Thin-Film Transistor Technologies
- Molecular Junctions and Nanostructures
Rensselaer Polytechnic Institute
2015-2024
Albany State University
2020
University at Albany, State University of New York
2020
Institute of Applied Astronomy
2014
Troy University
2001-2014
Korea Electronics Technology Institute
2003
Oak Ridge National Laboratory
1985
University of Wisconsin–Madison
1975-1980
Using a pump–probe method with 150 fs laser at the wavelength of 1.55 μm, we have experimentally demonstrated that single-walled carbon nanotubes (SWNT) an exciton decay time less than 1 ps and high third-order polarizability, which is reasonably interpreted as due to their azimuthal symmetry. These experimental results reveal SWNT polymer composite may be candidate material for high-quality subpicosecond all-optical switches.
A multistep diffusion-mediated process was developed to control the nucleation density, size, and lateral growth rate of WSe2 domains on c-plane sapphire for epitaxial large area monolayer films by gas source chemical vapor deposition (CVD). The consists an initial step followed annealing period in H2Se promote surface diffusion tungsten-containing species form oriented islands with uniform size controlled density. conditions were then adjusted suppress further laterally grow a fully...
We observed a scaling behavior during the shadowing growth of isolated Si, Co, Cu, and W nanocolumnar structures on Si substrates using oblique angle deposition with substrate rotation (also known as glancing or simply GLAD). The width columns, $W,$ grew function column length, $d,$ in power law form, $W\ensuremath{\sim}{d}^{p},$ where $p$ is exponent was measured to be $\ensuremath{\sim}0.28--0.34.$ It argued that without diffusion should lead $p=0.50$ would cross over 0.31 if one considers...
The hysteresis loops of epitaxially grown ultrathin Co films on a Cu(001) surface with magnetic anisotropy were measured in situ at room temperature under periodic external field by the magneto-optical Kerr-effect technique. A dynamic phase transition occurs high frequencies. At very low frequencies, \ensuremath{\Omega}, constant loop area exists. We also observed power-law scaling area,...
Three-dimensional nanostructures can be fabricated by the glancing angle deposition technique. By rotating substrate in both polar and azimuthal directions, one fabricate desired nanostructures, such as nano-rod arrays with different shapes, nano-spring arrays, even multilayer nanostructures. This method offers a fully three-dimensional control of nanostructure additional capability self-alignment. There is almost no limitation on materials that into In this presentation, we will discuss...
Dynamic scaling of magnetic hysteresis in a few monolayer thick Fe/Au(001) films was studied by using surface magneto-optic Kerr effect. For low values the frequency (\ensuremath{\Omega}) and amplitude (${\mathit{H}}_{0}$) an applied field, loss scales as A\ensuremath{\propto}${\mathit{H}}_{0}^{\mathrm{\ensuremath{\alpha}}}$${\mathrm{\ensuremath{\Omega}}}^{\mathrm{\ensuremath{\beta}}}$ with \ensuremath{\alpha}=0.59\ifmmode\pm\else\textpm\fi{}0.07...
One-dimensional nanoscale epitaxial arrays serve as a great model in studying fundamental physics and for emerging applications. With an increasing focus laid on the Cs-based inorganic halide perovskite out of its outstanding material stability, we have applied vapor phase epitaxy to grow well aligned horizontal CsPbX3 (X: Cl, Br, or I their mixed) nanowire large scale mica substrate. The as-grown features triangular prism morphology with typical length ranging from few tens micrometers...
Unlike the vast majority of transition metal dichalcogenides which are semiconductors, vanadium disulfide is metallic and conductive. This makes it particularly promising as an electrode material in lithium-ion batteries. However, exhibits poor stability due to large Peierls distortion during cycling. Here we report that flakes can be rendered stable electrochemical environment a battery by conformally coating them with ~2.5 nm thick titanium layer. Density functional theory calculations...
The knowledge on the influence of surface roughness and electron–phonon (el–ph) interaction electrical transport properties nanoscale metal films is important from both fundamental technological points view. Here we report a study temperature dependent electron copper by measuring resistivity with thickness ranging 4 to 500 nm. We show that residual resistivity, which independent, can be described quantitatively using measured vertical root-mean-square lateral correlation length in...
The V-VI binary chalcogenide, Sb2Se3, has attracted considerable attention for its applications in thin film optoelectronic devices because of unique 1D structure and remarkable properties. Herein, we report an Sb2Se3 epitaxially grown on a flexible mica substrate through relatively weak (van der Waals) interaction by vapor transport deposition. epitaxial films exhibit single (120) out-of-plane orientation 0.25° full width at half-maximum rocking curve X-ray diffraction, confirming the high...
Recently, antimony selenide (Sb2Se3) has exhibited an exciting potential for flexible photoelectric applications due to its unique one-dimensional (1D) chain-type crystal structure, low-cost constituents, and superior optoelectronic properties. The 1D structure endows Sb2Se3 with a strong anisotropy in carrier transport lasting mechanical deformation tolerance. control of the crystalline orientation film is essential requirement device performance optimization. However, current...
Through numerical calculations and Monte Carlo simulations, we examine the roughening behavior of a shadowing model, with lateral growth, for $(2+1)$-dimensional systems. The results show that growth exponent $\ensuremath{\beta}=1$ $\ensuremath{\beta}=0$ etching. For simulation tall columns are formed, correlation length obeys $\ensuremath{\xi}\ensuremath{\propto}(t\ensuremath{-}{t}_{0}{)}^{1/z},$ $1/z=0.93\ifmmode\pm\else\textpm\fi{}0.1.$ etching obtain $1/z=0,$ height-height function...
We report the creation of an unusual simple cubic β-phase W(100) nanorods with a pyramidal tip having four (110) facets using oblique-angle sputter deposition technique substrate rotation (also known as glancing-angle deposition). During deposition, both and α-phase W(110) islands exist at initial stages growth. The grow taller due to lower adatom mobility on these islands. survive in competition form isolated later This is contrast normal incidence, where only thermodynamically stable bcc...
We report the melting of nanorod arrays copper at temperatures much lower than its bulk point (1083°C). The Cu nanorods were produced by an oblique angle sputter deposition technique through a physical self-assembly mechanism due to shadowing effect. as-deposited ∼2300nm in length, ∼100nm diameter, and separated from each other with gaps varying between ∼10 ∼30nm. process was investigated analysis scanning electron microscopy, transmission x-ray diffraction measurements. Start premelting (or...
Ultrathin NbS2 films were synthesized from sputter-deposited ultrathin Nb on SiO2/Si and quartz substrates at 850 °C under sulfur vapor pressure. The structure surface composition of the characterized by grazing incidence X-ray diffraction photoelectron spectroscopy. have rhombohedral 3R-NbS2 are nearly stoichiometric. optical bandgaps samples determined ultraviolet–visible-near–infrared spectrometry to be in range ∼0.43 ∼0.90 eV indirect. This implies that film is semiconducting differs...
Novel materials suitable for optoelectronics are of great interest due to limited and diminishing energy resources the movement toward a green earth. We report simple film growth method tune S composition, x from 1 2 in semiconductor ultrathin SnSx films on quartz substrates, that is, single phase SnS, SnS2, mixed phases both SnS SnS2 by varying sulfurization temperature 150 500 °C. Due nature films, their structural optical properties characterized cross-checked multiple surface-sensitive...
Antimony (Sb) nanostructures, including islands, sheets, and thin films, of high crystallinity were epitaxially grown on single-crystalline graphene through van der Waals interactions. Two types substrates by chemical vapor deposition used, the as-grown Cu(111)/ c-sapphire transferred SiO2/Si. On graphene, ultrathin Sb resulted in two growth modes associated morphologies Sb. One was islands Volmer-Weber (VW) mode, other sheets Frank-van Merve (FM) mode. In contrast, only VW mode found a...
Through extensive $(2+1)$-dimensional numerical integration and Monte Carlo simulations, we compute the scaling exponents of a flux redistribution model that is proposed to describe plasma etching reactive ion surfaces. It found that, while surface morphology depends on conditions, roughness exponent \ensuremath{\alpha}, growth \ensuremath{\beta}, dynamic z are universal with regard details re-emission mechanism given by...