Wang Shu-Yan, Mao Ming-Wei, Wang Ke, Feng Zhan-Zu, Ma Ru-Han, Tang Yu-Long, Wang Qiang, Zhang Hao-Li
State Key Laboratory of Natural Product Chemistry (SKLNPC), Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Key Laboratory of Special Function Materials and Structure Design, Ministry of Education, Lanzhou University, Lanzhou 730000, China.
The Key Laboratory for Laser Plasmas (MOE), School of Physics and Astronomy, Collaborative Innovation Center of IFSA, Shanghai Jiao Tong University, Shanghai 200240, China.
ACS Appl Mater Interfaces. 2025 Jul 30;17(30):43424-43433. doi: 10.1021/acsami.5c08707. Epub 2025 Jul 16.
Space exploration is inseparable from advanced antiradiation materials with exceptional properties. Among these, nonlinear optical materials and devices, such as irradiation-resistant saturable absorbers (SAs), have garnered significant attention, particularly due to their critical role in integrated photonics for space use. This study presents a comprehensive evaluation of the space adaptability of two-dimensional (2D) WN under simulated space radiation conditions. When subjected to Co γ-ray irradiation at doses exceeding 45 years of accumulation in a typical low-Earth orbit, WN retained its robust third-order nonlinear saturable absorption across the visible- to near-infrared spectral range. Femtosecond transient absorption spectra offer a comprehensive view of the carrier dynamics of WN before and after irradiation, delving into radiation effects and damage mechanisms that are otherwise elusive to conventional techniques. The synthesized WN nanosheets were successfully employed as efficient SAs for Q-switched mode-locking in a Yb-doped fiber laser. The laser system operated at ∼1 μm NIR with high pulse energy and low saturation power, highlighting the remarkable potential of WN for integration into lasers, modulators, and other photonic devices. Notably, the irradiated WN demonstrated an identical mode-locking performance compared to its pristine counterpart. These findings provide valuable guidance for the rational design and screening of nonlinear optical materials capable of withstanding space radiation, offering significant implications for future space-based photonic applications.
太空探索离不开具有优异性能的先进抗辐射材料。其中，非线性光学材料及器件，如抗辐照饱和吸收体（SAs），受到了广泛关注，特别是因其在太空用集成光子学中的关键作用。本研究对二维（2D）WN在模拟太空辐射条件下的空间适应性进行了全面评估。当在典型低地球轨道上受到超过45年累积剂量的钴γ射线辐照时，WN在可见光至近红外光谱范围内保持了其强大的三阶非线性饱和吸收特性。飞秒瞬态吸收光谱全面展现了WN辐照前后的载流子动力学，深入探究了传统技术难以捉摸的辐射效应和损伤机制。合成的WN纳米片成功用作掺镱光纤激光器调Q锁模的高效饱和吸收体。该激光系统在近红外1μm左右工作，具有高脉冲能量和低饱和功率，突出了WN集成到激光器、调制器和其他光子器件中的巨大潜力。值得注意的是，辐照后的WN与其原始状态相比表现出相同的锁模性能。这些发现为合理设计和筛选能够耐受太空辐射的非线性光学材料提供了有价值的指导，对未来基于太空的光子应用具有重要意义。
