Fig. 1
From: Crossover from positive to negative optical torque in mesoscale optical matter
Light-driven self-organization of silver NPs into mesoscale optical matter arrays. a Schematic of rotation of an optical matter array in a liquid sample cell illuminated by a circularly polarized laser beam. Blue arrow represents the rotation direction of the electric vector of light, and green arrow indicates the rotation direction of an array formed by optical binding of ten NPs. The NPs are experimentally observed from the point of view of the incident light source, where the electric vector rotates counterclockwise in the imaging plane. We use the convention that this is termed left-handed circularly polarized (LHCP). b Dark-field optical images of representative optical matter arrays consisting of 2–13 150 nm diameter silver NPs. The scale bar is 1 µm
