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arXiv · 2607.14590

Second-Order Optical Nonlinearity of AlScN Films Grown By Molecular Beam Epitaxy

Joongwon Lee·Thai-Son Nguyen·Len van Deurzen·Debaditya Bhattacharya·Chandrashekhar Savant·Siddhartha Ghosh·Patrick Shea·Carl Bernard·Huili Grace Xing·Debdeep Jena·Farhan Rana
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Abstract

Alloys of AlN have rapidly emerged as a material platform for nonlinear optics. In this paper, we measure the second-order optical nonlinearity of AlScN films grown directly on nitrided c-plane sapphire by molecular beam epitaxy. This direct growth approach, which bypasses a thick AlN buffer layer, allows us to isolate the true nonlinear response of the AlScN film. Our results show a large enhancement of d31, but a suppression of d33 in AlScN films compared to AlN. We observe that d31 can be as high as 4.92 pm/V , which is 60 times larger than that of AlN. The development of AlScN-based photonic devices can enable energy-efficient nonlinear optical operations that can be epitaxially integrated with electronic and photonic devices based on Si, GaN and AlN.

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Joongwon Lee, Thai-Son Nguyen, Len van Deurzen, Debaditya Bhattacharya, Chandrashekhar Savant, Siddhartha Ghosh, Patrick Shea, Carl Bernard, Huili Grace Xing, Debdeep Jena, Farhan Rana. 2026-07-16. Second-Order Optical Nonlinearity of AlScN Films Grown By Molecular Beam Epitaxy. https://arxiv.org/abs/2607.14590

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