Movies clips [in avi]


Complete information and further update: http://www.phys.sinica.edu.tw/jctsai/gradient/)

Experiments on a gradient of vibration, frequency=25Hz; V-track with no tilt. The vibration strength (VS, defined in the main page) = 1.23

1) Movies showing a spatial divide around the transition, initiated at x=33cm [N=8, Topviews, 48X speed playback]

Demo 1 [57MB] , compressed [2MB]
Demo 2 [57MB] , compressed [2MB]
--- In some rare cases, the chain going to the right can rejoin the monotonic ratcheting on the left: Demo 3 [21MB] , compressed [1MB]
The vibration amplitude increases linearly rightwards, with markers showing the spatial scale at intervals of 1cm.

2) High-speed videos showing close-ups of the chain, captured originally at 2500fps [N=8, Sideviews with a 45-degree angle to the XY-plane]
Ground state , Gamma ~ 1.4 -- the roughly in-sync movements with the substrate, accompanying the monotonic ratcheting [0.4s in real time, displayed in 10s] [20MB]

Mode 1 , Gamma ~ 1.7 -- the swift reversed ratcheting "led" by the swinging end on the right
(a) [with spot illumination; 0.2s in real time, displayed in 5s] ; (b)[0.4s in real time, displayed in 10s]
Mode 2 , Gamma ~ 1.7 -- the tug-of-wars [with spot illumination; 0.2s in real time, displayed in 5s]

Further up the gradient, the coherence is lost and the response of the chain shows no recognizable patterns -- responses at excessive excitations (Gamma = 2.17)

3) The spatial divide with the reversal becomes less obvious as the length of the chain decreases. For N=3, the divide is no longer recognizable.
Initial x=33cm [41MB] , Initial x=38cm [41MB]