Successful Preparation of Co-BTE Metal–Organic Frameworks for All-Optical Nonlinear Switching and Photonic Diode Functions

The liquid-phase epitaxy (LPE) layer-by-layer method can be used to prepare metal-organic framework (MOF) materials suitable for nonlinear optical regulation due to its advantages of controllable thickness and smooth surface. In this study, Co-BTE MOF thin films were successfully synthesized by this technology, and their nonlinear control performance was studied by combining the spatial self-phase modulation method (SSPM). The results demonstrate that the Co-BTE MOF film has a significant nonlinear response with obvious third-order nonlinear optical effects observed. It was determined that the third-order nonlinear absorption coefficients of the Co-BTE MOF film were -0.03, 0.16, 0.33, and 0.04 cm/GW at wavelengths of 400, 532, 635, and 785 nm, respectively. To further investigate the nonlinear behavior of Co-BTE MOFs, the methods of SSPM and spatial cross-phase modulation (SXPM) were proposed to analyze their nonlinear regulation performance. Fortunately, the nonlinear properties of Co-BTE MOFs can be used to realize the functions of all-optical switches and photonic diodes, providing a reference for the development of nano-optoelectronic devices.