Publications of the Research Group Computational Photonics

Prof. Dr. Antonio Calà Lesina

Hyperpolarizability of plasmonic meta-atoms in metasurfaces

authored by
M. Saad Bin-Alam, Joshua Baxter, Kashif M. Awan, Antti Kiviniemi, Yaryna Mamchur, Antonino Calà Lesina, Kosmas L. Tsakmakidis, Mikko J. Huttunen, Lora Ramunno, Ksenia Dolgaleva

Plasmonic metasurfaces are promising as enablers of nanoscale nonlinear optics and flat nonlinear optical components. Nonlinear optical responses of such metasurfaces are determined by the nonlinear optical properties of individual nanostructured plasmonic meta-atoms, which are the building blocks of the metasurfaces. Unfortunately, no simple methods exist to determine the nonlinear coefficients (hyperpolarizabilities) of the meta-atoms hindering designing of nonlinear metasurfaces. Here, we develop the equivalent RLC circuit model of such meta-atoms to estimate their second-order nonlinear optical parameter i.e. the first-order hyperpolarizability in the optical spectral range. In parallel, we extract from second-harmonic generation experiments the spectrum of the 1st-order hyperpolarizabilities of individual meta-atoms consisting of asymmetrically shaped (elongated) plasmonic nanoprisms. Moreover, we verify our results using nonlinear hydrodynamic-FDTD and with calculations based on nonlinear scattering theory. All three approaches: analytical, experimental, and computational, yield results that agree very well. Our empirical RLC model can thus be used as a simple tool to enable efficient design of nonlinear plasmonic metasurfaces.

PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines
Hannover Centre for Optical Technologies (HOT)
External Organisation(s)
University of Ottawa
University of British Columbia
Tampere University
National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute" (NTUU KPI)
University of Athens
Publication date
Publication status
E-pub ahead of print
Electronic version(s) (Access: Open)