论文标题
通过局部层加热，在氧硝基硅薄膜中进行光学增强的第二次谐波生成
Optically enhanced second harmonic generation in silicon oxynitride thin films via local layer heating
论文作者
论文摘要
氮化硅中的第二个谐波生成（SHG）已在其他si3n4波导中的激光诱导的SHG增强方面进行了广泛的研究。这种增强已被归因于相干光藻效应引起的全光极。然而，尚未报道Si3n4薄膜的类似过程。我们的文章报道了在SI3N4薄膜中观察激光诱导的3倍SHG增强。观察到的增强功能具有许多类似于全光的特征，例如高度非线性功率依赖性，累积效应或与SI3N4-SI接口的连接。然而，低氧硅氧硝基薄膜的相同实验导致了复杂的行为，包括激光诱导的SHG还原。通过一项彻底的实验研究，观察到的结果归因于由多光子吸收引起的热诱导的SHG变化。这种行为表明，Sioxny-Si结构中光学诱导的SHG增强的起源可能是各种现象的复杂相互作用。
Strong second harmonic generation (SHG) in silicon nitride has been extensively studied-among others, in terms of laser-induced SHG enhancement in Si3N4 waveguides. This enhancement has been ascribed to the all-optical poling induced by the coherent photogalvanic effect. Yet, an analogous process for Si3N4 thin films has not been reported. Our article reports on the observation of laser-induced 3-fold SHG enhancement in Si3N4 thin films. The observed enhancement has many features similar to all-optical poling, such as highly nonlinear power dependence, cumulative effect, or connection to the Si3N4-Si interface. However, identical experiments for low-oxygen silicon oxynitride thin films lead to complex behavior, including laser-induced SHG reduction. By a thorough experimental study, the observed results were ascribed to heat-induced SHG variation caused by multiphoton absorption. Such behavior indicates that the origin of optically-induced SHG enhancement in SiOxNy-Si structures can be a complex interplay of various phenomena.
