山东大学陈峰团队研究了光伏光子晶格中多拓扑边态的非线性调谐。相关论文于2025年3月10日发表于《科学通报》杂志上。

拓扑和非线性的融合导致了复杂系统的突破性进展，为新发现和创新设备开发铺平了道路。然而，在具有多个拓扑间隙的复杂系统中，拓扑状态与自散焦非线性之间的相互作用尚未得到探索。

研究组展示了掺铁铌酸锂波导阵列中由光伏非线性调谐的两个不同的拓扑边缘孤子。通过建立具有两个拓扑间隙的光子非平凡装饰Su-Schrieffer-Heeger晶格，揭示了由这些间隙内的线性平方根边态导出的多个拓扑边孤子的出现。有趣的是，掺铁铌酸锂晶体中的体光伏效应可以产生驱动电光效应的内部电场，从而实现拓扑状态的实时动态操纵。

因此，研究组通过实验观察了具有多个拓扑间隙的系统内拓扑状态的完全自散焦非线性调谐过程，证明了局域化和非局域化之间的转变。该研究为探索非线性拓扑建立了一个新的平台，并为进一步研究其他有趣的非线性现象奠定了基础，提供了理论见解和实际应用。

附：英文原文

Title: Nonlinear tuning of multiple topological edge states in photovoltaic photonic lattices

Author: Wenchao Yan a, Yang Tan a, Feng Chen a

Issue&Volume: 2025/03/10

Abstract: The fusion of topology and nonlinearity has led to groundbreaking advancements in complex systems, paving the way for new discoveries and innovative device development. However, the interaction between topological states and self-defocusing nonlinearities in complex systems with multiple topological gaps has not yet been explored. Here we demonstrate two distinct topological edge solitons tuned by photovoltaic nonlinearity in Fe-doped lithium niobate waveguide arrays. By establishing a photonic nontrivial decorated Su-Schrieffer-Heeger lattice with two topological gaps, we reveal the emergence of multiple topological edge solitons derived from linear square-root edge states within these gaps. Interestingly, the bulk photovoltaic effect in Fe-doped lithium niobate crystals can generate an internal electric field that drives the electro-optical effect, enabling real-time dynamic manipulation of topological states. As a result, we experimentally observe the complete self-defocusing nonlinear tuning process of topological states within a system with multiple topological gaps, demonstrating the transitions between localization and delocalization. Our research establishes a novel platform for exploring nonlinear topology and sets the stage for further investigation into other intriguing nonlinear phenomena, offering both theoretical insights and practical applications.

DOI: 10.1016/j.scib.2025.03.018

Source: https://www.sciencedirect.com/science/article/pii/S2095927325002464