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arXiv · 2410.11033

Nonlinear van der Waals metasurfaces with resonantly enhanced light generation

Haonan Ling·Yuankai Tang·Xinyu Tian·Pavel Shafirin·Mozakkar Hossain·Polina P. Vabishchevich·Hayk Harutyunyan·Artur R. Davoyan
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Abstract

Efficient nonlinear wave mixing is of paramount importance for a wide range of applications. However, weak optical nonlinearities pose significant challenges for accessing nonlinear light-matter interaction in compact systems. Here, we experimentally study second harmonic generation in deeply subwavelength 3R-MoS2 metasurfaces (<\lambda/13 thick). Our measurements, supported by theoretical analysis, reveal a complex interplay and coupling between geometric resonances, optical extinction, and strong nonlinear susceptibility dispersion near excitons. We further demonstrate >150-fold enhancement in second harmonic signal at 740 nm driven by the A exciton resonance. Additionally, our theoretical studies predict an enhancement of more than 10^6 in second harmonic generation in <100 nm thick structures exhibiting bound states in the continuum resonance. These findings provide insight into accessing and harnessing the unprecedented 3R-MoS2 nonlinearities at a subwavelength scale, paving the way for ultracompact nonlinear photonic devices.

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Haonan Ling, Yuankai Tang, Xinyu Tian, Pavel Shafirin, Mozakkar Hossain, Polina P. Vabishchevich, Hayk Harutyunyan, Artur R. Davoyan. 2024-10-14. Nonlinear van der Waals metasurfaces with resonantly enhanced light generation. https://arxiv.org/abs/2410.11033

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