arXiv 1906.033572019-06-07physics.app-ph

极化x切薄膜锂酸盐的二次谐波显微术：了解对比度机制

Second harmonic microscopy of poled x-cut thin film lithium niobate: Understanding the contrast mechanism

Michael Ruesing, Jie Zhao, Shayan Mookherjea

DOI：: 10.1063/1.5113727

摘要：

锂离子薄膜是近年来研究的热点，对周期性极化薄膜的理解对于基础物理和器件的发展都是至关重要的。二次谐波（SH）显微镜允许非侵入性的可视化和铁电畴结构和壁的分析。虽然该技术是很好地理解在散装锂的氧化物，SH显微镜在薄膜的界面反射和共振增强，这取决于膜的厚度和基板材料的影响很大。我们提出了一个全面的分析SH显微镜在x切锂酸盐薄膜，基于一个完整的三维焦点计算，并占界面反射。我们发现，在背反射中的主导信号起源于通过反射观察到的共同传播的相位匹配过程，而不是直接检测到的反向传播的信号，如在散装样品。我们可以解释的域结构中的薄膜的几何形状的观察，特别是，我们表明，SH信号从薄极化膜允许明确区分领域，这是完全或仅部分反转的深度。

英文摘要：

Thin film lithium niobate is of great recent interest and an understanding of periodically poled thin-films is crucial for both fundamental physics and device developments. Second-harmonic (SH) microscopy allows for the non-invasive visualization and analysis of ferroelectric domain structures and walls. While the technique is well understood in bulk lithium niobate, SH microscopy in thin films is largely influenced by interfacial reflections and resonant enhancements, which depend on film thicknesses and the substrate materials. We present a comprehensive analysis of SH microscopy in x-cut lithium niobate thin films, based on a full three dimensional focus calculations, and accounting for interface reflections. We show that the dominant signal in back-reflection originates from a co-propagating phase-matched process observed through reflections, rather than direct detection of the counter-propagating signal as in bulk samples. We can explain the observation of domain structures in the thin film geometry, and in particular, we show that the SH signal from thin poled films allows to unambiguously distinguish areas, which are completely or only partly inverted in depth.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

摘要：

英文摘要：

相关论文