A Monte Carlo study of two-dimensional nanodroplet dynamics

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Journal Title
Journal ISSN
Volume Title
Master's thesis
Date
2007
Major/Subject
Computational Engineering
Mcode
S-114
Degree programme
Elektroniikan ja sähkötekniikan koulutusohjelma
Language
en
Pages
xvii, 74
Series
Abstract
This thesis discusses the dynamics of droplet translocation on lattices with potential gradient steps. Due to recent developments in manipulating droplets of a few nano-litres understanding the dynamics of nano-scale droplets has become important. The model used in this study consists of an Ising system simulated using the N-fold way method at very low temperatures. For creating new trial configurations we use Kawasaki dynamics. The potential gradients act over straight edges translocating droplets. Other geometries for the potentials producing unexpected results are also presented. When studying the droplet translocation over a potential we record the centre-of-mass location as well as modes of motion. The modes of motion describe how single particles move. Systems where the droplet is periodically connected in the direction of the step edge are used as a reference and to validate the model. The actual system investigated in this thesis is a two-dimensional free droplet driven by varying potentials on a solid surface. In order to characterise the dimensional behaviour of the free droplet, we perform a finite-size scaling and are able to achieve a data collapse when varying the field and dimensions of the droplet. The motivation for studying this system is to gain a better understanding of how droplets translocate over a step edge and to determine the necessary conditions for the ballistic translocation of a droplet on a surface.
Description
Supervisor
Kaski, Kimmo; Prof.
Thesis advisor
Linna, Riku; TkT
Keywords
nanodroplet, Monte Carlo, <em>N</em>-fold way, Ising, lattice gas, finite size scaling, driven diffusion, nanodroppe, Monte Carlo, <em>N</em>-fold way, Ising, lattice gas, finite-size scaling, driven diffusion
Other note
Citation
Permanent link to this item
https://urn.fi/urn:nbn:fi:tkk-010191