Ultrafast control of third-order optical nonlinearities in fishnet metamaterials

Abstract

Nonlinear photonic nanostructures that allow efficient all-optical switching are considered to be a prospective platform for novel building blocks in photonics. We performed time-resolved measurements of the photoinduced transient third-order nonlinear optical response of a fishnet metamaterial. The mutual influence of two non-collinear pulses exciting the magnetic resonance of the metamaterial was probed by detecting the third-harmonic radiation as a function of the time delay between pulses. Subpicosecond-scale dynamics of the metamaterial’s χ(3) was observed; the all-optical χ(3) modulation depth was found to be approximately 70% at a pump fluence of only 20 μJ/cm2.

Multipolar nonlinear nanophotonics

“…The idea of magnetic nonlinearities evolves, being further elaborated by the optics community. It finds implementations in doublelayer fishnet structures [155,[161][162][163], coupled metal nanodisks [154,164], and nanostrips [165]. These coupled plasmonic structures sustain antisymmetric oscillations of electron plasma leading to the magnetic-type resonances and the associated enhancement of the nonlinear response.…”

Third-harmonic generation from Mie-type resonances of isolated all-dielectric nanoparticles

“…Apart from the electric dipolar (ED) modes in simple geometries such as spheres [3,4] or dipole antennas [5,6], the modes with considerable magnetic dipolar (MD) moment [7][8][9] were extensively studied in the nonlinear-optical regime [10], being mainly associated with metamaterials and 'metamolecules' supporting optically induced magnetic response. Examples include the second-and thirdharmonic (TH) generation in split-ring resonators [11], fishnet metamaterials [12,13], split-hole cavities [14] and nanosandwiches [15]. A special contribution of MD modes to the nonlinear multipolar response of metasurfaces was indicated [15][16][17].…”

Engineered nonlinear materials using gold nanoantenna array

“…Note, that nonlinear response enhancement due to the intrinsic nonlinearity of plasmonic nanoantennas has previously been explored in some detail but still attracts great interest. These include studies on nanoparticle size-dependence of the nonlinear response 9 – 13 , from atomic clusters to plasmonic nanocrystals of Ag and Au 14 – 17 , optical Kerr-effect, inverse Faraday effect and nonlinear optical activity for metal nanoparticles and aggregates 18 , 19 , enhancing nonlinearity by using metasurfaces and metamaterial structures 20 , theory on figure-of-merit for nonlinear response 21 , core-shell for enhanced second-harmonic 22 , metasurface defined with e-beam lithography of α-Si:H nanorods for ultrafast spectral and polarization switching 23 .…”