Nonlinear all-optical technology is an ultimate route for the next-generation ultrafast signal processing of optical communication systems. New nonlinear functionalities need to be implemented in photonics, and complex oxides are considered as promising candidates due to their wide panel of attributes. In this context, yttria-stabilized zirconia (YSZ) stands out, thanks to its ability to be epitaxially grown on silicon, adapting the lattice for the crystalline oxide family of materials. We report, for the first time to the best of our knowledge, a detailed theoretical and experimental study about the third-order nonlinear susceptibility in crystalline YSZ. Via self-phase modulation-induced broadening and considering the in-plane orientation of YSZ, we experimentally obtained an effective Kerr coefficient of n^2YSZ=4.0±2×10−19 m2·W−1 in an 8% (mole fraction) YSZ waveguide. In agreement with the theoretically predicted n^2YSZ=1.3×10−19 m2· W−1, the third-order nonlinear coefficient of YSZ is comparable with the one of silicon nitride, which is already being used in nonlinear optics. These promising results are a new step toward the implementation of functional oxides for nonlinear optical applications.

中文翻译：

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晶体氧化钇稳定氧化锆的三阶非线性光学磁化率

非线性全光技术是下一代光通信系统超快信号处理的终极途径。需要在光子学中实现新的非线性功能，并且复合氧化物由于其广泛的属性而被认为是有前途的候选者。在这种情况下，氧化钇稳定的氧化锆 (YSZ) 脱颖而出，因为它能够在硅上外延生长，使晶格适应晶体氧化物系列材料。据我们所知，我们首次报告了关于晶体 YSZ 中三阶非线性磁化率的详细理论和实验研究。通过自相位调制引起的展宽并考虑到 YSZ 的面内取向，我们通过实验获得了 n^2YSZ=4 的有效克尔系数。0±2×10-19 m2·W-1 在 8%（摩尔分数）YSZ 波导中。与理论预测的 n^2YSZ=1.3×10-19 m2·W-1 一致，YSZ 的三阶非线性系数与已经用于非线性光学的氮化硅相当。这些有希望的结果是实现功能性氧化物用于非线性光学应用的新步骤。