Yulia sokolov, Derek Frydel, Haim Diamant and Yael Roichman

F I I

Radiation pressure

Gradientforce

Phasegradient

Dipole in electromagnetic field

Radiation pressure

SLM

objective

L=6

• R~L• Trot~L

2

objective

laser

Non-equilibrium, hydrodynamic interactionphonons, single file diffusion

1 3cos3 11

16 2 1 cos[ ]iji

ij

a

K R

,3sin3

16 2 1 cos[ ]i j

ij

iV a

K

The model:

•Paired particles with “pair” mobility.•Equidistanced.•Collective mode.•Stokeslet approximation.

1 2

2

1

8ij ij

r rG

r r

( 4)4

1

( 2)4

1

11 ( )

8 2 2

1 ( )8 2

1 3cos( )( )

1 cos( )

4

12

12

N

n

N

n

QrK nx

R

QrK nx

R

nxK nx

nx

xN

NevenQ r

collective mobility

NoddQ r

Fitting parameter

6 r

Drag of a single sphere in fluid

Q r

Drag of coupled spheres in fluid

Q

da

ParticlesBrownianicHydrodynam FFFdt

dvm

Yulia sokolov, Derek frydel, Haim Diamant and Yael Roichman, in preparation.

θ

I – one particle diffusion α=1II - caging effect, subdiffusion 0.5<α<1III - collective diffusion α=1

Hydrodynamic Interactions give rise to a pseudo-potential in this out-of-equilibrium system, whichresult in particle pairing.

For an even number of particles there exists a mode inwhich particles rotate as a “crystal”. Is the systemminimizing dissipation while maximizing stability?

Single file diffusion exists in driven systems. We seethe crossover to collective diffusion in this smallsystem.