Fig. 1. A sketch of the light torque geometry. Here the induced dipole p will move to align with the electric field E to minimize energy. Hence, a torque τ = p × E exists about an axis out of the plane of the paper.

Fig. 2. Image sequences showing the three different types of motion. In each frame a ⁺ symbol labels the orientation of the rod and the scale bar is 3 μm. (a) Discrete nanorod manipulation: the light polarization is discretely oriented by a manual rotation of the polarization optic at the following angles with respect to a horizontal line: (1) 45, (2) 90, (3) 135, (4) 180. (b) Nanomotor behavior: the rod rotates in response to a rotating polarization light torque. (c) Nanorocker behavior: here the rod rocks in response to a rotating polarization light torque. In frame # 9, the nanorod has completed one full period of rocking.

Fig. 3. A plot of the angular range ∆θ versus laser polarization rotation frequency Ω for a single nanorod undergoing rocking motion. Inset: A plot of the angle versus time for the glass nanorod in Fig. 2(c) - operated in nanorocker mode.

Fig. 4. (1.28 Mb) Polarized-light torque nanomotor: a glass rod in an optical trap rotating due to the torque applied by rotating the polarization of the trapping light. Note the interrupted, or saltatory, motion of the nanorod. The glass rod is 2.5 μm long and 260 nm in diameter.