Figure 1. Photo-thermal overview.

(a) Photo-thermal actuation schematic. Three thin GNP/PDMS composite strips are mounted with their upper ends fixed to a rigid plate. The free end of sample [1] is unrestricted, while samples [2] and [3] have a weight attached, thus inducing pre-strain into the composite actuator. [3] Illumination via an IR LED results in energy transduction to the polymeric chains, causing a contraction in the actuator (and thus usable work). (b) Simplified single-axis nanopositioner layout. A laser displacement sensor is used to measure stage position. Independently controlled diodes on either side of the stage allow for differential positive or negative axis stage motion.