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arXiv · 2007.01558

Large few-layer hexagonal boron nitride flakes for nonlinear optics

Nils Bernhardt·Sejeong Kim·Johannes E. Froch·Simon White·Ngoc My Hanh Duong·Zhe He·Bo Chen·Jin Liu·Igor Aharonovich·Alexander S. Solntsev
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Abstract

Hexagonal boron nitride (hBN) is a layered dielectric material with a wide range of applications in optics and photonics. In this work, we demonstrate a fabrication method for few-layer hBN flakes with areas up to 5000 $\rm \mu m$. We show that hBN in this form can be integrated with photonic microstructures: as an example, we use a circular Bragg grating (CBG). The layer quality of the exfoliated hBN flake on a CBG is confirmed by second-harmonic generation (SHG) microscopy. We show that the SHG signal is uniform across the hBN sample outside the CBG and is amplified in the centre of the CBG.

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Nils Bernhardt, Sejeong Kim, Johannes E. Froch, Simon White, Ngoc My Hanh Duong, Zhe He, Bo Chen, Jin Liu, Igor Aharonovich, Alexander S. Solntsev. 2020-07-03. Large few-layer hexagonal boron nitride flakes for nonlinear optics. https://doi.org/10.1364/ol.416564

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