高性能的光限幅对激光防护应用来说非常重要。虽然光限幅相关的研究持续了几十年, 但是绝大多数的已知光限幅材料无法兼顾低限幅阈值、高线性透过率和宽带、超快响应。从实验和理论上报道一种基于共轭扭曲并苯分子的多功能光限幅材料。研究结果显示, 借助等效三光子吸收, 该材料能够在480~700 nm的光谱范围内实现光限幅并具备快速的响应能力。此外, 样品还同时具备低限幅阈值(0.15 J/cm2)和极高的线性透过率(532 nm时92%)。该光限幅材料集以上所有优点于一身, 在用于人眼和光子器件的超快激光防护领域具有巨大的前景。

High-performance optical limiting (OL) is of great importance in laser protection application. Although the research of OL lasts for decades, most existing material can not possess all the desired merits such as low threshold, high linear transmittance, especially broadband and ultrafast respondence. Here, the multi-functional OL in conjugated twistacene was reported through experiments and theory. Results show that broadband OL with fast switching speed can be achieved from 480 nm-700 nm based on effective three-photon absorption. Moreover, low OL thresholds (0.15 J/cm2) and extremely high linear transmittance (92% at 532 nm) are simultaneously observed. All these combined advantages in one material shows tremendous potential in ultrafast laser protection for human eye and photonic devices.