Ultrafast optical control of nonlinear dielectric nanoantennas

Efficient ultrafast reconfiguration of the second-harmonic generation of AlGaAs nonlinear nanoantennas operating at 1550 nm telecom wavelength, is achieved by ultrafast interband photoexcitation with femtosecond visible pulses. The combination of broadband transient transmittivity, time-revolved second harmonic generation, and nonlinear optics nanoscale modeling, allows to track the ultrafast modulation of the second harmonic signal, into the nanoscale charge carrier dynamics at the base of a giant permittivity change at the semiconducting band edge