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arXiv · 2504.17980

Robust Poling and Frequency Conversion on Thin-Film Periodically Poled Lithium Tantalate

Anna Shelton·C. J. Xin·Keith Powell·Jiayu Yang·Shengyuan Lu·Neil Sinclair·Marko Loncar
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Abstract

We explore a robust fabrication process for periodically-poled thin-film lithium tantalate (PP-TFLT) by systematically varying fabrication parameters and confirming the quality of inverted domains with second-harmonic microscopy (SHM). We find a periodic poling recipe that can be applied to both acoustic-grade and optical-grade film, electrode material, and presence of an oxide interlayer. By using a single high-voltage electrical pulse with peak voltage time of 10 ms or less and a ramp-down time of 90 s, rectangular poling domains are established and stabilized in the PP-TFLT. We employ our robust periodic poling process in a controllable pole-after-etch approach to produce PP-TFLT ridge waveguides with normalized second harmonic generation (SHG) conversion efficiencies of 208 %W-1cm-2 from 1550 nm to 775 nm in line with the theoretical value of 244 %W-1cm-2. This work establishes a high-performance poling process and demonstrates telecommunications band SHG for thin-film lithium tantalate, expanding the capabilities of the platform for frequency mixing applications in quantum photonics, sensing, and spectroscopy.

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Anna Shelton, C. J. Xin, Keith Powell, Jiayu Yang, Shengyuan Lu, Neil Sinclair, Marko Loncar. 2025-04-24. Robust Poling and Frequency Conversion on Thin-Film Periodically Poled Lithium Tantalate. https://arxiv.org/abs/2504.17980

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