AI 中文总结
研究利用X切薄膜钽酸锂的拉曼响应，通过设计耦合定义的耗散重新配置拉曼和克尔过程阈值，实现了超宽带梳状光谱及多色可见光发射，将其从阻碍变为助力，确立其为强大单片平台。
AI 中文摘要
X切薄膜钽酸锂（TFLT）具有三阶非线性、电光效应和高光损伤阈值的独特组合。然而，其强烈的拉曼响应一直阻碍着宽带克尔梳的产生。在此，我们通过设计耦合定义的耗散来利用这种固有的拉曼响应。这使我们能够在不改变本征微谐振器色散的情况下重新配置拉曼和克尔过程的相对阈值。通过这种耦合工程阈值控制，我们可以有意地获得不同的梳状状态，从纯克尔梳到拉曼 - 克尔协同宽带梳。我们展示了一个跨越450nm的克尔梳和一个跨越650nm的拉曼 - 克尔梳，这是迄今为止在X切TFLT平台上报道的最宽的梳状光谱。此外，在强耦合器件中，我们表明单个近红外泵浦可以通过级联二次和频过程产生跨多个波段（从紫光到红光）的可见光发射。我们的工作表明，强烈的拉曼响应可以从寄生竞争者转变为实现更宽梳状光谱和产生多色可见光的启用机制。这项工作将X切TFLT确立为用于非线性光源、电光功能和复杂光子系统的强大单片平台。
英文摘要
X-cut thin-film lithium tantalate (TFLT) offers a unique combination of third nonlinearity, electro-optic effects, and a high optical damage threshold. However, its strong Raman response has historically hindered broadband Kerr comb generation. Here, we leverage this inherent Raman response by engineering coupling-defined dissipation. This allows us to reconfigure the relative thresholds of Raman and Kerr processes without modifying the intrinsic microresonator dispersion. Through this coupling-engineered threshold control, we can deliberately access distinct comb states, ranging from pure Kerr combs to Raman-Kerr synergistic broadband combs. We demonstrate a Kerr comb spanning 450 nm and a Raman-Kerr comb spanning 650 nm, representing the broadest combs reported to date on X-cut TFLT platforms. Moreover, in strongly coupled devices, we show that a single near-infrared pump can generate visible emission across multiple bands (from violet to red) via cascaded second sum-frequency processes. Our work demonstrates that a strong Raman response can be transformed from a parasitic competitor into an enabling mechanism for achieving broader comb spectra and generating polychromatic visible light. This work establishes X-cut TFLT as a powerful monolithic platform for nonlinear light sources, electro-optic functions, and complex photonic systems.
