High-order wave mixing in solid-state platforms gather increasing importance due to the development of advanced lasers and integrated photonic circuit for both classical and quantum information. However, the high-order wave mixing is generally inefficient in solids under weak pump. Here, we observed the presence of phase matching of five-wave mixing (5WM) propagating in a zinc oxide (ZnO) microwire. The 5WM signal is enhanced by 2–3 orders of magnitude under the phase matching conditions, reaching an absolute conversion efficiency of 1.7 × 10−13 when the peak pumping power density is about 106 W/cm2. The propagation of multiple nonlinear signals, including sum frequency generation, third harmonic generation, four-wave mixing etc., benefited from both the large nonlinear coefficients and the wide transparent window of ZnO, implies the possibility of developing cascaded nonlinear process under higher pumping. This study enriches the ZnO platform for integrated nonlinear nanophotonics.

中文翻译：

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氧化锌微丝中的相位匹配五波混频


由于先进激光器和用于经典信息和量子信息的集成光子电路的发展，固态平台中的高阶波混频变得越来越重要。然而，高阶波混合在弱泵浦下的固体中通常效率较低。在这里，我们观察到氧化锌 (ZnO) 微丝中传播的五波混频 (5WM) 存在相位匹配。在相位匹配条件下，5WM信号增强了2-3个数量级，当峰值泵浦功率密度约为106 W/cm2时，绝对转换效率达到1.7 × 10−13。多种非线性信号的传播，包括和频产生、三次谐波产生、四波混频等，得益于ZnO的大非线性系数和宽透明窗口，意味着在更高泵浦下发展级联非线性过程的可能性。这项研究丰富了集成非线性纳米光子学的 ZnO 平台。