random deposition = simplest possible growth model pick a random column. add a particle on top of...

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Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column 2 / 1 ~ ~ t t h

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Page 1: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

Random deposition = simplest possible growth model

Pick a random column.Add a particle on top of that column

2/1~

~

t

th

Page 2: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

Random deposition with surface diffusion

4/1~

~

t

th

Particle can move a short distance to find a more stable configuration.

Pick a random column i.Compare h(i) and h(i+1).Particle is added onto whichever is lower. If they are equal, add to coulmn i or i+1 with equal probability.

Page 3: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

Restricted Solid On Solid Model - RSOS

Neighbouring sites may not have a height difference greater than 1.

Pick a random column i.Add a particle only if h(i) h(i-1) and h(i) h(i+1).Otherwise pick a new column.

c

Page 4: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

Eden model – simple model for tumor growth or epidemic spread

c

Each site that is a neighbour of an occupied site has an equal probability of being filled.

Make a list of neighbour sites (red).Pick one at random. Add it to cluster (blue).Neighbours of this site then become red….

There can be more than one growth site in a column. Can get overhangs.

Page 5: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

c

Ballistic deposition

Particles fall vertically from above and stick when they touch a particle below or a neighbour on one side.

Pick a column i. Let particle fall till it touches a neighbour. Possible growth sites are indicated in red. Only one possible site per column.

Page 6: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

c

Diffusion Limited Aggregation - DLA

A particles starts a long way from surface.It diffuses until it first touches the surface. If it moves too far away, another particle is started.

Page 7: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

fractal dimension 1.7

Page 8: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

Dielectric breakdown model= 1Same as DLA

Page 9: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

Dielectric breakdown model= 4

Page 10: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

Dielectric breakdown model= 2

Page 11: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

Dielectric breakdown model= 1

Page 12: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

Dielectric breakdown model= 0.1

Page 13: Random deposition = simplest possible growth model Pick a random column. Add a particle on top of that column

Dielectric breakdown model= 0Same as Eden model