Ali Mohamed A, Liu Xiaofeng, Li Yang, Ren Jinjun, Qiu Jianrong
State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
Inorg Chem. 2020 Jun 15;59(12):8380-8386. doi: 10.1021/acs.inorgchem.0c00806. Epub 2020 Jun 1.
Recently, metal-organic frameworks (MOFs) have been confirmed to be stable in a vitreous state, thus stimulating growing interest in the discovery of the physicochemical properties of these newly explored types of glasses. Herein, we examine the nonlinear-optical (NLO) response of Zn- and Zn-Co-based zeolitic imidazolate framework-62 (ZIF-62) glasses using an open-aperture Z-scan technique. We reveal that the Zn-ZIF-62 glass does not characterize a saturable absorption feature (1030 nm femtosecond laser) owing to its low optical absorption in the near-infrared (NIR) spectral region. In contrast, a NIR absorption band (1100 nm) has been observed in Zn-Co-ZIF-62 glass, which exhibits a strong NLO response with a high modulation depth of 63.85%. We attribute the observed NLO response to transient saturation of the T(F) level of Co ions upon femtosecond laser excitation. The intriguing NLO properties of this MOF glass may enable potential applications in the photonics fields for sensing and optical modulation.
最近，金属有机框架材料（MOFs）已被证实处于玻璃态时是稳定的，这激发了人们对探索这些新型玻璃的物理化学性质的浓厚兴趣。在此，我们使用开孔Z扫描技术研究了基于锌和锌钴的沸石咪唑酯骨架-62（ZIF-62）玻璃的非线性光学（NLO）响应。我们发现，由于Zn-ZIF-62玻璃在近红外（NIR）光谱区域的低光吸收，它不具有饱和吸收特性（1030 nm飞秒激光）。相比之下，在Zn-Co-ZIF-62玻璃中观察到一个近红外吸收带（1100 nm），其具有强烈的NLO响应，调制深度高达63.85%。我们将观察到的NLO响应归因于飞秒激光激发下Co离子的T(F)能级的瞬态饱和。这种MOF玻璃有趣的NLO特性可能使其在光子学领域的传感和光调制方面具有潜在应用。
