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Updated: Jun 16, 2025

Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
Nonlinear Chiral Metasurfaces Based on Structured van der Waals Materials
Pavel Tonkaev1, Ivan Toftul1, Zhuoyuan Lu2
1Nonlinear Physics Center, Research School of Physics, Australian National University, Canberra, Australian Capital Territory 2601, Australia.
Abstract:
Nonlinear chiral photonics explores the nonlinear response of chiral structures, and it offers a pathway to novel optical functionalities not accessible through linear or achiral systems. Here we present the first application of nanostructured van der Waals materials to nonlinear chiral photonics. We demonstrate the 3 orders of magnitude enhancement of the third-harmonic generation from hBN metasurfaces driven by quasi-bound states in the continuum and accompanied by strong nonlinear circular dichroism at the resonances. This novel platform for chiral metaphotonics can be employed for achieving large circular dichroism combined with high-efficiency harmonic generation in a broad frequency range.
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