Optical nanoantenna arrays loaded with nonlinear materials

Abstract

Optical nanoantennas loaded by nanoparticles are used to provide large and controllable field enhancement at the nanoscale. Here we show how the introduction of nonlinearities at the nanoload may realize a whole set of all-optical nanoscale functionalities, such as memories, switches and transistors, as a function of whether the nanoantenna is excited "below" or "above" its resonance frequency. After discussing the main features of this nonlinear nanoantenna operation, we employ its bistable and self-tunable response in a planar array design, which may constitute different nonlinear devices and functionalities of significant interest for optical computing applications.

Modulatable optical radiators and metasurfaces based on quantum nanoantennas

“…Although the individual response of a nanoantenna provides various exciting possibilities, its scattering cross section associated with total scattered power is typically very minimal due to its extremely small size. For this reason, nanoantenna experiments are usually demonstrated with the two-dimensional (2-D) planar array of nanoantennas, representing a type of optical metasurface or metamaterial with custom-designed optical properties for imaging and holography [16][17][18], optical switching [14,19,20], polarization and phase controlling [10,11,21,22], energy harvesting [23][24][25][26][27], and nonlinear optical [14,[28][29][30] applications.…”

Hotspot-mediated ultrafast nonlinear control of multifrequency plasmonic nanoantennas

“…While these nonlinearities of the plasmonic metal can be employed for modulation devices, they are generally associated with a considerable thermal loading of the device and are accompanied by slow thermal relaxation effects. Several schemes have been proposed theoretically for active nanoantenna devices coupled to an external Kerr-medium [25][26][27]. Experimentally, such an ultrafast antenna-enhanced Kerr nonlinearity has not yet been reported.…”

Plasmonic circuits for manipulating optical information

“…This is analogous to capacitive and inductive loading of the antenna [196,197]. When loaded with non-linear materials, it has been shown theoretically that optical antennas can exhibit bistability [198]. Tunable plasmonic antennas were created from two suspended wires and changing their separation with an applied voltage [199].…”