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 Selected recent publications (6)
 Theory and models of film growth (2)
 Morphology of films (2)
 Dewetting (2)
 Mathematical Modeling (2)

 Selfassembly (2)
 Liquid bilayer films (1)
 Thermocapillary convection (1)
 Interfacial stabil ity (1)
 Ultrathin metal lms (1)
 Selforganization (1)
 Nanopatterning (1)
 Graphene oxide (1)
 Carbon nanotubes (1)
 Presentations (1)
 Stability analysis (1)
 PDE model (1)
 Nanotechnology (1)
 Pulsed laser irradiation (1)
Articles 1  22 of 22
FullText Articles in Physics
Interplay Of Quantum Size Effect, Anisotropy And Surface Stress Shapes The Instability Of Thin Metal Films, Mikhail Khenner
Interplay Of Quantum Size Effect, Anisotropy And Surface Stress Shapes The Instability Of Thin Metal Films, Mikhail Khenner
Mathematics Faculty Publications
Morphological instability of a planar surface ([111], [011], or [001]) of an ultrathin metal film is studied in a parameter space formed by three major effects (the quantum size effect, the surface energy anisotropy and the surface stress) that influence a film dewetting. The analysis is based on the extended Mullins equation, where the effects are cast as functions of the film thickness. The formulation of the quantum size effect (Z. Zhang et al., PRL 80, 5381 (1998)) includes the oscillation of the surface energy with thickness caused by electrons confinement. By systematically comparing the effects, their contributions into the ...
Investigation Of Carbon Nanomaterials Embedded In A Cementitious Matrix, Clarissa A. Roe
Investigation Of Carbon Nanomaterials Embedded In A Cementitious Matrix, Clarissa A. Roe
Masters Theses & Specialist Projects
The objective of this thesis was to investigate whether the addition of carbon nanofibers had an effect on the splitting tensile strength of HydroStone gypsum concrete. The carbon nanofibers used were singlewalled carbon nanotubes (SWNT), buckminsterfullerene (C60), and graphene oxide (GO). Evidence of the nanofibers interacting with gypsum crystals in a connective manner was identified in both 1 mm thick concrete discs and concrete columns possessing a height of 2 in and a diameter of 1 in. Before imaging, the columns were subjected to a splitting tensile strength test. The results illustrate that while there is a general decrease in ...
Model For Computing Kinetics Of The Graphene Edge Epitaxial Growth On Copper, Mikhail Khenner
Model For Computing Kinetics Of The Graphene Edge Epitaxial Growth On Copper, Mikhail Khenner
Mathematics Faculty Publications
A basic kinetic model that incorporates a coupled dynamics of the carbon atoms and dimers ona copper surface is used to compute growth of a singlelayer graphene island. The speed of theisland's edge advancement on Cu[111] and Cu[100] surfaces is computed as a function of the growthtemperature and pressure. Spatially resolved concentration pro les of the atoms and dimers aredetermined, and the contributions provided by these species to the growth speed are discussed.Island growth in the conditions of a thermal cycling is studied.
Controlling Nanoparticles Formation In Molten Metallic Bilayers By PulsedLaser Interference Heating, Mikhail Khenner, Sagar Yadavali, Ramki Kalyanaraman
Controlling Nanoparticles Formation In Molten Metallic Bilayers By PulsedLaser Interference Heating, Mikhail Khenner, Sagar Yadavali, Ramki Kalyanaraman
Mathematics Faculty Publications
The impacts of the twobeam interference heating on the number of coreshell and embedded nanoparticles and on nanostructure coarsening are studied numerically based on the nonlinear dynamical model for dewetting of the pulsedlaser irradiated, thin (< 20 nm) metallic bilayers. The model incorporates thermocapillary forces and disjoining pressures, and assumes dewetting from the optically transparent substrate atop of the reflective support layer, which results in the complicated dependence of light reflectivity and absorption on the thicknesses of the layers. Stabilizing thermocapillary effect is due to the local thicknessdependent, steady state temperature profile in the liquid, which is derived based on the mean substrate temperature estimated from the elaborate thermal model of transient heating and melting/freezing. Linear stability analysis of the model equations set for Ag/Co bilayer predicts the dewetting length scales in the qualitative agreement with experiment.
Formation Of Organized Nanostructures From Unstable Bilayers Of Thin Metallic Liquids, Mikhail Khenner, Sagar Yadavali, Ramki Kalyanaraman
Formation Of Organized Nanostructures From Unstable Bilayers Of Thin Metallic Liquids, Mikhail Khenner, Sagar Yadavali, Ramki Kalyanaraman
Mathematics Faculty Publications
Dewetting of pulsedlaser irradiated, thin (< 20 nm), optically reflective metallic bilayers on an optically transparent substrate with a reflective support layer is studied within the lubrication equations model. A steadystate bilayer film thickness (h) dependent temperature profile is derived based on the mean substrate temperature estimated from the elaborate thermal model of transient heating and melting/freezing. Large thermocapillary forces are observed along the plane of the liquidliquid and liquidgas interfaces due to this hdependent temperature, which, in turn, is strongly influenced by the hdependent laser light reflection and absorption. Consequently the dewetting is a result of the competition between thermocapillary and intermolecular forces. A linear analysis of the dewetting length scales established that the nonisothermal calculations better predict the experimental results as compared to the isothermal case within the bounding Hamaker coefficients. Subsequently, a computational nonlinear dynamics study of the dewetting pathway was performed for Ag/Co and Co/Ag bilayer systems to predict the morphology evolution. We found that the systems evolve towards formation of different morphologies, including coreshell, embedded, or stacked nanostructure morphologies.
Stability Of A Strongly Anisotropic Thin Epitaxial Film In A Wetting Interaction With Elastic Substrate, Mikhail Khenner, Wondimu Tekalign, Margo Levine
Stability Of A Strongly Anisotropic Thin Epitaxial Film In A Wetting Interaction With Elastic Substrate, Mikhail Khenner, Wondimu Tekalign, Margo Levine
Mathematics Faculty Publications
The linear dispersion relation for longwave surface perturbations, as derived by Levine et al. Phys. Rev. B 75, 205312 (2007) is extended to include a smooth surface energy anisotropy function with a variable anisotropy strength (from weak to strong, such that sharp corners and slightly curved facets occur on the corresponding Wulff shape). Through detailed parametric studies it is shown that a combination of a wetting interaction and strong anisotropy, and even a wetting interaction alone results in complicated linear stability characteristics of strained and unstrained films.
Modeling Diverse Physics Of Nanoparticle SelfAssembly In Pulsed LaserIrradiated Metallic Films, Mikhail Khenner
Modeling Diverse Physics Of Nanoparticle SelfAssembly In Pulsed LaserIrradiated Metallic Films, Mikhail Khenner
Mathematics Faculty Publications
Presents physics behind dewetting of thin liquid films and mathematical/computational modeling tools (Educational/Research presentation for senior physics majors).
Stability Of A Strongly Anisotropic Thin Epitaxial Film In A Wetting Interaction With Elastic Substrate, Mikhail Khenner, Wondimu T. Tekalign, Margo S. Levine
Stability Of A Strongly Anisotropic Thin Epitaxial Film In A Wetting Interaction With Elastic Substrate, Mikhail Khenner, Wondimu T. Tekalign, Margo S. Levine
Mathematics Faculty Publications
The linear dispersion relation for longwave surface perturbations, as derived by Levine et al. Phys. Rev. B 75, 205312 (2007) is extended to include a smooth surface energy anisotropy function with a variable anisotropy strength (from weak to strong, such that sharp corners and slightly curved facets occur on the corresponding Wulff shape). Through detailed parametric studies it is shown that a combination of a wetting interaction and strong anisotropy, and even a wetting interaction alone results in complicated linear stability characteristics of strained and unstrained films.
Morphological Evolution Of SingleCrystal Ultrathin Solid Films, Mikhail Khenner
Morphological Evolution Of SingleCrystal Ultrathin Solid Films, Mikhail Khenner
Mathematics Faculty Publications
An introduction to mathematical modeling of ultrathin solid films and the role of such modeling in nanotechnologies: Educational/Research presentation for senior physics majors
Morphological Evolution Of SingleCrystal Ultrathin Solid Films, Mikhail Khenner
Morphological Evolution Of SingleCrystal Ultrathin Solid Films, Mikhail Khenner
Mathematics Faculty Publications
An introduction to mathematical modeling of ultrathin solid films and the role of such modeling in nanotechnologies: Educational presentation for senior physics majors
Oscillatory And Monotonic Modes Of LongWave Marangoni Convection In A Thin Film, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev
Oscillatory And Monotonic Modes Of LongWave Marangoni Convection In A Thin Film, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev
Mathematics Faculty Publications
We study longwave Marangoni convection in a layer heated from below. Using the scaling k=O Bi, where k is the wave number and Bi is the Biot number, we derive a set of amplitude equations. Analysis of this set shows presence of monotonic and oscillatory modes of instability. Oscillatory mode has not been previously found for such direction of heating. Studies of weakly nonlinear dynamics demonstrate that stable steady and oscillatory patterns can be found near the stability threshold.
Oscillatory And Monotonic Modes Of LongWave Marangoni Convection In A Thin Film, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev
Oscillatory And Monotonic Modes Of LongWave Marangoni Convection In A Thin Film, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev
Mathematics Faculty Publications
We study longwave Marangoni convection in a layer heated from below. Using the scaling k=O Bi, where k is the wave number and Bi is the Biot number, we derive a set of amplitude equations. Analysis of this set shows presence of monotonic and oscillatory modes of instability. Oscillatory mode has not been previously found for such direction of heating. Studies of weakly nonlinear dynamics demonstrate that stable steady and oscillatory patterns can be found near the stability threshold.
Thermocapillary Effects In Driven Dewetting And SelfAssembly Of Pulsed LaserIrradiated Metallic Films, Mikhail Khenner
Thermocapillary Effects In Driven Dewetting And SelfAssembly Of Pulsed LaserIrradiated Metallic Films, Mikhail Khenner
Mathematics Faculty Publications
A mathematical model for the evolution of pulsed laserirradiated, molten metallic films has been developed using the lubrication theory. The heat transfer problem that incorporates the absorbed heat from a single laser beam or the interfering laser beams is solved analytically. Using this temperature field, we derive the 3D longwave evolution PDE for the film height. To get insights into dynamics of dewetting, we study the 2D version of the evolution equation by means of a linear stability analysis and by numerical simulations. The stabilizing and destabilizing effects of various system parameters, such as the reflectivity, the peak laser beam ...
Thermocapillary Effects In Driven Dewetting And SelfAssembly Of Pulsed LaserIrradiated Metallic Films, Mikhail Khenner
Thermocapillary Effects In Driven Dewetting And SelfAssembly Of Pulsed LaserIrradiated Metallic Films, Mikhail Khenner
Mathematics Faculty Publications
A mathematical model for the evolution of pulsed laserirradiated, molten metallic films has been developed using the lubrication theory. The heat transfer problem that incorporates the absorbed heat from a single laser beam or the interfering laser beams is solved analytically. Using this temperature field, we derive the 3D longwave evolution PDE for the film height. To get insights into dynamics of dewetting, we study the 2D version of the evolution equation by means of a linear stability analysis and by numerical simulations. The stabilizing and destabilizing effects of various system parameters, such as the reflectivity, the peak laser beam ...
Thermocapillary Effects In Driven Dewetting And SelfAssembly Of Pulsed LaserIrradiated Metallic Films, Mikhail Khenner
Thermocapillary Effects In Driven Dewetting And SelfAssembly Of Pulsed LaserIrradiated Metallic Films, Mikhail Khenner
Mathematics Faculty Publications
A mathematical model for the evolution of pulsed laserirradiated, molten metallic films has been developed using the lubrication theory. The heat transfer problem that incorporates the absorbed heat from a single laser beam or the interfering laser beams is solved analytically. Using this temperature field, we derive the 3D longwave evolution PDE for the film height. To get insights into dynamics of dewetting, we study the 2D version of the evolution equation by means of a linear stability analysis and by numerical simulations. The stabilizing and destabilizing effects of various system parameters, such as the reflectivity, the peak laser beam ...
Thermocapillary Effects In Driven Dewetting And SelfAssembly Of Pulsed LaserIrradiated Metallic Films, Agegnehu Atena, Mikhail Khenner
Thermocapillary Effects In Driven Dewetting And SelfAssembly Of Pulsed LaserIrradiated Metallic Films, Agegnehu Atena, Mikhail Khenner
Mathematics Faculty Publications
In this paper the lubricationtype dynamical model is developed of a molten, pulsed laserirradiated metallic film. The heat transfer problem that incorporates the absorbed heat from a single beam or interfering beams is solved analytically. Using this temperature field, we derive the 3D longwave evolution PDE for the film height. To get insights into dynamics of dewetting, we study the 2D version of the evolution equation by means of a linear stability analysis and by numerical simulations. The stabilizing and destabilizing effects of various system parameters, such as the peak laser beam intensity, the film optical thickness, the Biot and ...
Thermocapillary Effects In Driven Dewetting And SelfAssembly Of Pulsed LaserIrradiated Metallic Films, Agegnehu Atena, Mikhail Khenner
Thermocapillary Effects In Driven Dewetting And SelfAssembly Of Pulsed LaserIrradiated Metallic Films, Agegnehu Atena, Mikhail Khenner
Mathematics Faculty Publications
In this paper the lubricationtype dynamical model is developed of a molten, pulsed laserirradiated metallic film. The heat transfer problem that incorporates the absorbed heat from a single beam or interfering beams is solved analytically. Using this temperature field, we derive the 3D longwave evolution PDE for the film height. To get insights into dynamics of dewetting, we study the 2D version of the evolution equation by means of a linear stability analysis and by numerical simulations. The stabilizing and destabilizing effects of various system parameters, such as the peak laser beam intensity, the film optical thickness, the Biot and ...
Morphologies And Kinetics Of A Dewetting Ultrathin Solid Film, Mikhail Khenner
Morphologies And Kinetics Of A Dewetting Ultrathin Solid Film, Mikhail Khenner
Mathematics Faculty Publications
The surface evolution model based on geometric partial differential equation is used to numerically study the kinetics of dewetting and dynamic morphologies for the localized pinhole defect in the surface of the ultrathin solid film with the strongly anisotropic surface energy. Depending on parameters such as the initial depth and width of the pinole, the strength of the attractive substrate potential and the strength of the surface energy anisotropy, the pinhole may either extend to the substrate and thus rupture the film, or evolve to the quasiequilibrium shape while the rest of the film surface undergoes phase separation into a ...
Enhanced Stability Of A Dewetting Thin Liquid Film In A SingleFrequency Vibration Field, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev
Enhanced Stability Of A Dewetting Thin Liquid Film In A SingleFrequency Vibration Field, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev
Mathematics Faculty Publications
Dynamics of a thin dewetting liquid film on a vertically oscillating substrate is considered. We assume moderate vibration frequency and large (compared to the mean film thickness) vibration amplitude. Using the lubrication approximation and the averaging method, we formulate the coupled sets of equations governing the pulsatile and the averaged fluid flows in the film, and then derive the nonlinear amplitude equation for the averaged film thickness. We show that there exists a window in the frequencyamplitude domain where the parametric and shearflow instabilities of the pulsatile flow do not emerge. As a consequence, in this window the averaged description ...
Enhanced Stability Of A Dewetting Thin Liquid Film In A SingleFrequency Vibration Field, Mikhail Khenner
Enhanced Stability Of A Dewetting Thin Liquid Film In A SingleFrequency Vibration Field, Mikhail Khenner
Mathematics Faculty Publications
Dynamics of a thin dewetting liquid film on a vertically oscillating substrate is considered. We assume moderate vibration frequency and large (compared to the mean film thickness) vibration amplitude. Using the lubrication approximation and the averaging method, we formulate the coupled sets of equations governing the pulsatile and the averaged fluid flows in the film, and then derive the nonlinear amplitude equation for the averaged film thickness. We show that there exists a window in the frequencyamplitude domain where the parametric and shearflow instabilities of the pulsatile flow do not emerge. As a consequence, in this window the averaged description ...
Morphologies And Kinetics Of A Dewetting Ultrathin Solid Film, Mikhail Khenner
Morphologies And Kinetics Of A Dewetting Ultrathin Solid Film, Mikhail Khenner
Mathematics Faculty Publications
The surface evolution model based on geometric partial differential equation is used to numerically study the kinetics of dewetting and dynamic morphologies for the localized pinhole defect in the surface of the ultrathin solid film with the strongly anisotropic surface energy. Depending on parameters such as the initial depth and width of the pinole, the strength of the attractive substrate potential and the strength of the surface energy anisotropy, the pinhole may either extend to the substrate and thus rupture the film, or evolve to the quasiequilibrium shape while the rest of the film surface undergoes phase separation into a ...
Enhanced Stability Of A Dewetting Thin Liquid Film In A SingleFrequency Vibration Field, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev
Enhanced Stability Of A Dewetting Thin Liquid Film In A SingleFrequency Vibration Field, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev
Mathematics Faculty Publications
Dynamics of a thin dewetting liquid film on a vertically oscillating substrate is considered. We assume moderate vibration frequency and large (compared to the mean film thickness) vibration amplitude. Using the lubrication approximation and the averaging method, we formulate the coupled sets of equations governing the pulsatile and the averaged fluid flows in the film, and then derive the nonlinear amplitude equation for the averaged film thickness. We show that there exists a window in the frequencyamplitude domain where the parametric and shearflow instabilities of the pulsatile flow do not emerge. As a consequence, in this window the averaged description ...