Figure 2: Dynamics of the microparticle in the steam engine.
From: A microscopic steam engine implemented in an optical tweezer
(a) Selected frames from a singe cycle of a 3-μm particle. Scale bar, 10 μm. (b) Full trajectory for the cycle shown in a. (c) Trajectory for a few cycles projected in the xy plane. (d) distance 
measured relative to the position of the geometrical focus. See Supplementary Movies 1 and 2.
