Article

Enhancing the Nonlinear Optical Response Using Multifrequency Gold-Nanowire Antennas

Institute of Optics, University of Rochester, Rochester, New York 14627, USA.
Physical Review Letters (Impact Factor: 7.73). 05/2012; 108(21):217403. DOI: 10.1103/PhysRevLett.108.217403

ABSTRACT We introduce and experimentally demonstrate the concept of multifrequency optical antennas that are designed for controlling the nonlinear response of materials. These antennas consist of two arms of different lengths, each resonant with one of the incoming frequencies. They are embedded in a nonlinear medium (indium tin oxide) that acts as a receiver. Because the two arms have different spectral resonances, tuning of the antenna gap size has minimal effect on the linear optical properties. However, it strongly affects the nonlinear response. Thus, by employing antenna elements with different spectral resonances, we provide a strategy to decouple the nonlinear response of nanomaterials from their linear optical properties.

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