English
Related papers

Related papers: Transition from anomalous kinetics towards Fickian…

200 papers

We study agitated frictional disks in two dimensions with the aim of developing a scaling theory for their diffusion over time. As a function of the area fraction $\phi$ and mean-square velocity fluctuations $\langle v^2\rangle$ the…

Soft Condensed Matter · Physics 2019-10-09 H. G. E. Hentschel , Itamar Procaccia , Saikat Roy

The dynamics of water in electrolyte solutions exhibits a striking, ion-specific anomaly: the diffusion coefficient of water is enhanced relative to the neat liquid in chaotropic CsI solutions, yet suppressed in kosmotropic NaCl solutions.…

Chemical Physics · Physics 2026-04-17 Massimo Ciacchi , Ilnur Saitov , Nico Di Fonte , Isabella Daidone , Carlo Pierleoni

The diffusion of small solvent molecules in glassy polymers may take on a variety of different forms. Fickian, anomalous, Case II, and super Case II diffusion have all been observed, and theoretical models exist that describe each specific…

Soft Condensed Matter · Physics 2017-07-27 Jiayuan Miao , Mesfin Tsige , Philip L. Taylor

Using random walk simulations we explore diffusive transport through monodisperse sphere packings over a range of packing fractions, $\phi$, in the vicinity of the jamming transition at $\phi_{c}$. Various diffusion properties are computed…

Statistical Mechanics · Physics 2015-09-02 Dan S. Bolintineanu , Gary S. Grest , Jeremy B. Lechman , Leonardo E. Silbert

A study is presented of the structural changes occurring as a function of the annealing conditions in hydrogenated amorphous Si/Ge multilayers prepared by sputtering. Annealing changes the structure of the as-deposited multilayer except for…

Materials Science · Physics 2009-02-12 C. Frigeri , M. Serenyi , A. Csik , Z. Erdelyi , D. L. Beke , L. Nasi

We study the continuum limit in 2+1 dimensions of nanoscale anisotropic diffusion processes on crystal surfaces relaxing to become flat below roughening. Our main result is a continuum law for the surface flux in terms of a new…

Materials Science · Physics 2009-11-13 John Quah , Dionisios Margetis

We present analytical results for the biased diffusion of particles moving under a constant force in a randomly layered medium. The influence of this medium on the particle dynamics is modeled by a piecewise constant random force. The…

Statistical Mechanics · Physics 2010-02-10 S. I. Denisov , H. Kantz

For a substance diffusing on a curved surface, we obtain an explicit relation valid for very small values of the time, between the local concentration, the diffusion coefficient, the intrinsic spatial curvature and the time. We recover the…

Biological Physics · Physics 2009-11-10 J. Balakrishnan

Silicene, a 2D analogue of graphene, has spurred a tremendous research interest in the scientific community for its unique properties essential for next generation electronic devices. In this work, for the first time, we present a molecular…

Materials Science · Physics 2017-11-22 Tawfiqur Rakib , Sourav Saha , Mohammad Motalab , Satyajit Mojumder , Md Mahbubul Islam

We have studied the diffusion inside the silica network of sodium atoms initially located outside the surfaces of an amorphous silica film. We have focused our attention on structural and dynamical quantities, and we have found that the…

Disordered Systems and Neural Networks · Physics 2009-11-10 Michael Rarivomanantsoa , Philippe Jund , Remi Jullien

Simultaneous measurement of self-diffusion of iron and nitrogen in amorphous iron nitride (Fe86N14) using secondary ion mass spectroscopy (SIMS) technique has been done. In addition neutron reflectivity (NR) technique was employed to study…

We perform molecular dynamics simulations to understand the translational and rotational diffusion of Janus nanoparticles at the interface between two immiscible fluids. Considering spherical particles with different affinity to fluid…

Fluid Dynamics · Physics 2016-05-04 Hossein Rezvantalab , German Drazer , Shahab Shojaei-Zadeh

Normal and anomalous diffusion are ubiquitous in many complex systems [1] . Here, we define a time and space generalized diffusion equation (GDE), which uses fractional-time derivatives and transformed d-path Laplacian operators on…

Physics and Society · Physics 2022-02-02 Fernando Diaz-Diaz , Ernesto Estrada

The dynamics of amorphous silicon at low temperatures can be characterized by a sequence of discrete activated events, through which the topological network is locally reorganized. Using the activation-relaxation technique, we create more…

Condensed Matter · Physics 2009-10-31 G. T. Barkema , Normand Mousseau

Amorphous silicon (a-Si) models are analyzed for structural, electronic and vibrational characteristics. Several models of various sizes have been computationally fabricated for this analysis. It is shown that a recently developed…

Disordered Systems and Neural Networks · Physics 2018-11-29 Dale Igram , Bishal Bhattarai , Parthapratim Biswas , D. A. Drabold

The formation of Ni(Pt)silicides on a Si(001) surface is investigated using an ab initio approach. After deposition of a Ni overlayer alloyed with Pt, the calculations reveal fast diffusion of Ni atoms into the Si lattice, which leads…

Materials Science · Physics 2013-08-13 M. Christensen , V. Eyert , C. Freeman , E. Wimmer , A. Jain , J. Blatchford , D. Riley , J. Shaw

The crossover from single-file diffusion, where the mean-square displacement scales as <x^2> ~t^(1/2), to normal Fickian diffusion, where <x^2>~t$, is studied as a function of channel width for colloidal particles. By comparing Brownian…

Soft Condensed Matter · Physics 2010-01-07 J. Sané , J. T. Padding , A. A. Louis

We have analyzed the atomic rearrangements underlying self-diffusion in amorphous Si during annealing using tight-binding molecular dynamics simulations. Two types of amorphous samples with different structural features were used to analyze…

Materials Science · Physics 2015-05-20 Iván Santos , Luis A. Marqués , Lourdes Pelaz , Luciano Colombo

We report the observation of a stepwise "melting" of the low-temperature Na-vacancy order in the layered transition metal oxide Na0.7CoO2. High-resolution neutron powder diffraction indicates the existence of two first-order structural…

Dielectric spectroscopy of CaCu3Ti4O12 was performed spanning broad ranges of temperature (10-300K) and frequency (0.5Hz-2MHz). We attribute the permittivity step-fall to the evolution of Kirkwood-Fr\"oehlich dipole-correlations; reducing…

Materials Science · Physics 2014-09-23 A. M. Awasthi , Jitender Kumar