V-shaped gold nanoantennas are the functional components of plasmonic metasurfaces, which are capable of manipulating light in unprecedented ways. Designing a metasurface requires the custom arrangement of individual antennas with controlled shape and orientation. Here, we show how highly crystalline gold nanorods in solution can be bent, one-by-one, into a V-shaped geometry and printed to the surface of a solid support through a combination of plasmonic heating and optical force. Significantly, we demonstrate that both the bending angle and the orientation of each rod-antenna can be adjusted independent from each other by tuning the laser intensity and polarization. This approach is applicable for the patterning of V-shaped plasmonic antennas on almost any substrate, which holds great potential for the fabrication of ultrathin optical components and devices.

A highly reproducible photoresponse is observed in nanocrystalline SnO 2 thick films sensitized with CdSe quantum dots. The effect of the SnO 2 matrix microstructure on the photoconductivity kinetics and photoresponse amplitude is demonstrated. The photoresponse of the sensitized SnO 2 thick films reaches more than two orders of magnitude under illumination with the wavelength of the excitonic transition of the quantum dots. Long-term photoconductivity kinetics and photoresponse dependence on illumination intensity reveal power-law behavior inherent to the disordered nature of SnO 2 . The photoconductivity of the samples rises with the coarsening of the granular structure of the SnO 2 matrix. At the saturation region, the photoresponse amplitude remains stable under 10 4 pulses of illumination switching, demonstrating a remarkably high stability.

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