The engine's page

You would like to see the engines of

(R14): Atomic scale engines: Cars and wheels
M. Porto, M. Urbakh, and J. Klafter, Phys. Rev. Lett. 84, 6058-6061 (2000).
(Covered by Physics News Update No. 490 of June 22, 2000 and Nature Science Update of July 3, 2000)
(R23): Hopping motion of interacting particles: From time dependent interaction to directed transport
M. Porto, M. Urbakh, and J. Klafter, Phys. Rev. E 65, 011108 (2002) (6 pages).
(R43): Mesoscale engines by nonlinear friction
D. Fleishman, J. Klafter, M. Porto, and M. Urbakh, Nano Lett. 7, 837-842 (2007).
(P8): Atomic scale engines: Taking a turn
M. Porto, M. Urbakh, and J. Klafter, Acta Phys. Pol. B 32, 295-306 (2001).
(XXIV International School of Theoretical Physics `Transport Phenomena from Quantum to Classical Regimes', Ustron, Poland, September 25 to October 1, 2000)
(P11): Motors on the molecular scale
M. Porto, M. Urbakh, and J. Klafter, J. Luminescence 94-95, 137-142 (2001).
(International Conference on `Dynamical Processes in Excited States of Solids', Lyon, France, July 1 to 4, 2001)

at work? Have a look at the following MPEG files

see `The short chain moving' (420x260, 632 kB)
The surface potential is shown in color code, where blue means low and red means high potential. The three particles are shown in green, and each of the two `springs' is show as a `piston'. The chain performs two steps to the right.
see `The `car' moving' (420x340, 2.6 MB)
The surface potential is shown in color code, where blue means low and red means high potential. The nine particles are shown in green, and each of the six `springs' is show as a `piston'. During the motion, six `springs' of three parallel `chains' are driven coherently. The `car' performs two steps to the right, one step down, two steps left, and one step up, coming back to its initial position.
see `The longer chain transporting a cargo' (900x260, 3.1 MB)
The surface potential is shown in color code, where blue means low and red means high potential. The active part is shown in green, and the cargo is shown in magenta. The engine together with the cargo performs one step to the right, and it takes five cyles of the engine's motion to pull the cargo completely over the barrier. The sequence is taken out of a continuous motion, so that the engine part is not in a relaxed state at the beginning.
see `The chain running in circles' (420x420, 3.7 MB)
The surface potential is shown in color code, where blue means low and red means high potential. The three particles are shown in green, and each of the two `springs' is show as a `piston'. The chain runs in circles.
see `The `wheel' rotating' (420x420, 621 kB)
The potential is shown as a line, where the radius indicates the height of the potential. The three particles are colored in red, green, and blue. The `springs' are omitted for clearness. The colored arrows indicate how far the particles have moved with respect to their initial position.
see `The `wheel' rotating again' (420x420, 2.1 MB)
The potential is shown as a line, where the radius indicates the height of the potential. The three particles are colored in red, green, and blue. Each of the three `springs' is show as a `piston'. The `wheel' rotates one full rotation counterclockwise.

You might also be interested to read the Physics News Update No. 490, Story No. 1: `Atomic Scale Locomotives' or Nature Science Update of July 3, 2000: `Fast forward'.

You might also be interested to have a look on the list of publications related to molecular machines.