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arXiv · 1902.09060

Second-harmonic generation in multilayer hexagonal boron nitride flakes

Sejeong Kim·Johannes E. Fröch·Augustine Gardner·Chi Li·Igor Aharonovich·Alexander S. Solntsev
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Abstract

We report second-harmonic generation (SHG) from thick hexagonal boron nitride (hBN) flakes with approximately 109-111 layers. The resulting effective second-order susceptibility is similar to previously reported few-layer experiments. This confirms that thick hBN flakes can serve as a platform for nonlinear optics, which is useful because thick flakes are easy to exfoliate while retaining a large flake size. We also show spatial second-harmonic maps revealing that SHG remains a useful tool for the characterization of the layer structure even in the case of a large number of layers.

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Sejeong Kim, Johannes E. Fröch, Augustine Gardner, Chi Li, Igor Aharonovich, Alexander S. Solntsev. 2019-11-07. Second-harmonic generation in multilayer hexagonal boron nitride flakes. https://doi.org/10.1364/ol.44.005792

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