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arXiv · 2401.10381

Resonant Fully dielectric metasurfaces for ultrafast Terahertz pulse generation

Luke Peters·Davide Rocco·Luana Olivieri·Unai Arregui Leon·Vittorio Cecconi·Luca Carletti·Carlo Gigli·Giuseppe Della Valle·Antonio Cutrona·Juan Sebastian Totero Gongora·Giuseppe Leo·Alessia Pasquazi·Costantino De Angelis·Marco Peccianti
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Abstract

Metasurfaces represent a new frontier in materials science paving for unprecedented methods of controlling electromagnetic waves, with a range of applications spanning from sensing to imaging and communications. For pulsed terahertz generation, metasurfaces offer a gateway to tuneable thin emitters that can be utilised for large-area imaging, microscopy and spectroscopy. In literature THz-emitting metasurfaces generally exhibit high absorption, being based either on metals or on semiconductors excited in highly resonant regimes. Here we propose the use of a fully dielectric semiconductor exploiting morphology-mediated resonances and inherent quadratic nonlinear response. Our system exhibits a remarkable 40-fold efficiency enhancement compared to the unpatterned at the peak of the optimised wavelength range, demonstrating its potential as scalable emitter design.

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Luke Peters, Davide Rocco, Luana Olivieri, Unai Arregui Leon, Vittorio Cecconi, Luca Carletti, Carlo Gigli, Giuseppe Della Valle, Antonio Cutrona, Juan Sebastian Totero Gongora, Giuseppe Leo, Alessia Pasquazi, Costantino De Angelis, Marco Peccianti. 2024-01-18. Resonant Fully dielectric metasurfaces for ultrafast Terahertz pulse generation. https://doi.org/10.1002/adom.202303148

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