Extraordinary nonlinear absorption in 3D bowtie nanoantennas.

ABSTRACT: This paper reports that arrays of three-dimensional (3D), bowtie-shaped Au nanoparticle dimers can exhibit extremely high nonlinear absorption. Near-field interactions across the gap of the 3D bowties at the localized surface plasmon resonance wavelengths resulted in an increase of more than 4 orders of magnitude in local field intensity. The imaginary part of the third-order nonlinear susceptibility (Im ?((3))) for the 3D bowtie arrays embedded in a dielectric material was measured to be 10(-4) esu, more than 2 orders of magnitude higher than reported for other metal nanoparticle-dielectric composites. Moreover, 3D dimers with increased nanoscale structure (such as folding) exhibited increased optical nonlinearity. These 3D nanoantennas can be used as critical elements for nanoscale nonlinear optical devices.

SUBMITTER: Suh JY 

PROVIDER: S-EPMC3256284 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature