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Effects of surface thermodynamics on hydrogen isotope exchange kinetics in palladium: Particle and flow models
Palladium is an important material for separation of hydrogen from other gases, separation of hydrogen isotopes, and for hydrogen storage. Its main advantages are its high selectivity and rapid, highly reversible uptake and release of hydrogen at near-ambient temperatures and pressures. Toward a more comprehensive understanding of its behavior, we present particle and continuum multiphysics mat...


Temporal resolution criterion for correctly simulating relativistic electron motion in a high-intensity laser field
Particle-in-cell codes are now standard tools for studying ultra-intenselaser-plasma interactions. Motivated by direct laser acceleration of electronsin sub-critical plasmas, we examine temporal resolution requirements that mustbe satisfied to accurately calculate electron dynamics in strong laser fields. Using the motion of a single electron in a perfect plane electromagnetic waveas a test pro...
High sensitivity, low-systematics atom interferometers using Bragg diffraction and Bloch oscillations
We describe a new scheme for atom interferometry based on both large-momentumtransfer Bragg beam splitters and Bloch oscillations. Combining the advantagesof previous approaches to recoil-sensitive interferometers, we increase thesignal and suppress a systematic phase shift caused by Bragg diffraction atleast 60-fold, matching experiment to theory; the systematic shift can beeliminated from Mac...


Tunable Geometric Fano Resonances in a Metal/Insulator Stack
A metal-insulator-metal-insulator stack is shown to have a Fano resonance inthe angular domain. The metal/insulator stack consists of two interactingsubsystems, a metallic waveguide mode and a surface plasmon mode, coupled by afinite layer metal film. The two modes in close spatial proximity interferedestructively resulting in level repulsion of two metal/insulator stack modes. By adding a coup...
Differentiating surface and bulk interactions in nanoplasmonic interferometric sensor arrays
Detecting specific target analytes and differentiating them from interferingbackground effects is a crucial but challenging task in complex multi-componentsolutions commonly encountered in environmental, chemical, biological, andmedical sensing applications. Here we present a simple nanoplasmonicinterferometric sensor platform that can differentiate the adsorption of a thinprotein layer on the ...


Towards a precession driven dynamo experiment
The most ambitious project within the DREsden Sodium facility for DYNamo andthermohydraulic studies (DRESDYN) at Helmholtz-Zentrum Dresden-Rossendorf(HZDR) is the set-up of a precession-driven dynamo experiment. After discussingthe scientific background and some results of water pre-experiments andnumerical predictions, we focus on the numerous structural and design problemsof the machine. We a...
Past and future sea-level rise along the coast of North Carolina, United States
Focusing on factors that cause relative sea-level (RSL) rise to differ fromthe global mean, we evaluate RSL trajectories for North Carolina, UnitedStates, in the context of tide gauge and geological sea-level proxy recordsspanning the last $mathord{sim}$11,000 years. RSL rise was fastest($mathord{sim}$7 mm/yr) during the early Holocene and decreased over time. During the Common Era before the 1...

On the energy partition in oscillations and waves
A class of generally nonlinear dynamical systems is considered, for which theLagrangian is represented as a sum of homogeneous functions of thedisplacements and their derivatives. It is shown that an energy partition as asingle relation follows directly from the Euler-Lagrange equation in itsgeneral form. It is defined solely by the homogeneity orders. If the potentialenergy is represented by a...
Specific Absorbed Fractions of Electrons and Photons for Rad-HUMAN Phantom Using Monte Carlo Method
The specific absorbed fractions (SAF) for self- and cross-irradiation areeffective tools for the internal dose estimation of inhalation and ingestionintakes of radionuclides. A set of SAFs of photon and electron were calculatedusing the Rad-HUMAN phantom, a computational voxel phantom of Chinese adultfemale and created using the color photographic image of the Chinese VisibleHuman (CVH) data se...

A systematic bias in the calculation of spectral density from a 3D spatial grid
The energy spectral density $E(k)$, where $k$ is the spatial wave number, isa well-known diagnostic of homogeneous turbulence and magnetohydrodynamicturbulence. However in most of the curves plotted by different authors, somesystematic kinks can be observed at $k=9$, $k=15$ and $k=19$. We claim thatthese kinks have no physical meaning, and are in fact the signature of themethod which is used to...
Subwavelength-thick Lenses with High Numerical Apertures and Large Efficiency Based on High Contrast Transmitarrays
We report subwavelength-thick, polarization insensitive micro-lensesoperating at telecom wavelength with focal spots as small as 0.57 wavelengthsand measured focusing efficiency up to 82%. The lens design is based on highcontrast transmitarrays that enable control of optical phase fronts withsubwavelength spatial resolution. A rigorous method for ultra-thin lens design,and the trade-off between...

A mechanism for magnetic field stochastization and energy release during an edge pedestal collapse
On the basis of three-dimensional nonlinear magnetohydrodynamic simulations,we propose a new dynamical process leading to the stochastization of magneticfields during an edge pedestal collapse. Primary tearing modes are shown togrow by extracting kinetic energy of unstable ballooning modes, eventuallyleading to the island overlap. Secondary tearing modes, which are generatedthrough a coherent n...
A Generalized Linear Transport Model for Spatially-Correlated Stochastic Media
We formulate a new model for transport in stochastic media with long-rangespatial correlations where exponential attenuation (controlling the propagationpart of the transport) becomes power law. Direct transmission over opticaldistance $tau(s)$, for fixed physical distance $s$, thus becomes$(1+tau(s)/a)^{-a}$, with standard exponential decay recovered when$atoinfty$. Atmospheric turbulence phen...
Realization of "Trapped Rainbow" in 1D slab waveguide with Surface Dispersion Engineering
We present a design of a one dimensional dielectric waveguide that can trap abroad band light pulse with different frequency component stored at differentpositions, effectively forming a "trapped rainbow"[1]. The spectrum of therainbow covers the whole visible range. To do this, we first show that thedispersion of a $text{SiO}_2$ waveguide with a Si grating placed on top can beengineered by the...
Inertial magnetohydrodynamics
A version of extended magnetohydrodynamics (MHD) that incorporates electroninertia is obtained by constructing an action principle. Unlike MHD whichfreezes in magnetic flux, the present theory freezes in an alternative fluxrelated to the electron canonical momentum. The associated Hamiltonianformulation is derived and reduced models that have previously been used todescribe collisionless reconn...