In this paper, we report the large optical nonlinearities of zeolitic imidazolate framework-67 (ZIF-67) in the near-infrared (NIR) region. Typical Z-scan techniques were carried out to determine the nonlinear optical (NLO) performance of ZIF-67 at 1.06 and 1.34 μm. With increased excitation pump intensity, a reinforcement of the saturable absorption was observed. With the excitation wavelength at 1.06 μm, the largest effective nonlinear absorption coefficient β_eff was −0.85 cm GW⁻¹ and the highest modulation depth ΔT was 29.1%. For a wavelength of 1.34 μm, the maximum β_eff and ΔT of ZIF-67 were −0.87 cm GW⁻¹ and 19.8%, respectively. The complete optical limiting behavior of ZIF-67 was also investigated with increased pump intensity. The large two-photon absorption (TPA) cross sections (∼8.5 × 10⁶ GM) made ZIF-67 suitable for possible applications as optical limiting devices. In addition, the nonlinear refractive index n₂, and real and imaginary parts of the third-order NLO susceptibility were also determined. This work explores the NLO properties of ZIF-67 in the NIR regime comprehensively and will benefit potential NLO-based applications of optical modulators, optoelectronics and optical limiting devices.

中文翻译：

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沸石咪唑盐骨架67在近红外区域的光学非线性

在本文中，我们报道了在近红外（NIR）区域中，沸石咪唑盐骨架67（ZIF-67）的较大光学非线性。进行了典型的Z扫描技术以确定ZIF-67在1.06和1.34μm处的非线性光学（NLO）性能。随着激励泵浦强度的增加，可饱和吸收得到增强。与1.06微米的激发波长，最大有效非线性吸收系数β _EFF WAS -0.85厘米GW ^-1和最高调制深度Δ Ť率为29.1％。对于1.34微米波长，最大β _EFF和Δ Ť的ZIF-67分别为-0.87厘米GW ^-1和19.8％。还通过增加泵浦强度研究了ZIF-67的完整光学极限行为。大的两光子吸收（TPA）横截面（约8.5×10 ⁶ GM）使ZIF-67适合作为光学限制装置的可能应用。此外，还确定了非线性折射率n ₂以及三阶NLO磁化率的实部和虚部。这项工作全面探讨了NIF体制中ZIF-67的NLO特性，并将有益于光调制器，光电和光限制器件在基于NLO的潜在应用。