Nonlinear Fano-Resonant Dielectric Metasurfaces.
Strong nonlinear light-matter interaction is highly sought-after for a variety of applications including lasing and all-optical light modulation. Recently, resonant plasmonic structures have been considered promising candidates for enhancing nonlinear optical processes due to their ability to greatly enhance the optical near-field; however, their small mode volumes prevent the inherently large nonlinear susceptibility of the metal from being efficiently exploited. Here, we present an alternative approach that utilizes a Fano-resonant silicon metasurface. The metasurface results in strong near-field enhancement within the volume of the silicon resonator while minimizing two photon absorption. We measure a third harmonic generation enhancement factor of 1.5 × 10(5) with respect to an unpatterned silicon film and an absolute conversion efficiency of 1.2 × 10(-6) with a peak pump intensity of 3.2 GW cm(-2). The enhanced nonlinearity, combined with a sharp linear transmittance spectrum, results in transmission modulation with a modulation depth of 36%. The modulation mechanism is studied by pump-probe experiments.
Interdisciplinary Materials Science Program, Vanderbilt University , Nashville, Tennessee 37212, United States.
Yuanmu
Y
Yang
Department of Electrical Engineering and Computer Science, Vanderbilt University , Nashville, Tennessee 37212, United States.
Wenyi
W
Wang
Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
Abdelaziz
A
Boulesbaa
Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
Ivan I
II
Kravchenko
Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
Dayrl P
DP
Briggs
Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
Alexander
A
Puretzky
Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
David
D
Geohegan
Department of Mechanical Engineering, Vanderbilt University , Nashville, Tennessee 37212, United States.
Jason
J
Valentine
Fano resonance; Metamaterial; dielectric antenna; third harmonic generation