An Exceptionally Stable Porous Indium-Organic Framework with Enhanced Third-Order Nonlinear Optical Performance

Area of Science:

• Materials Science
• Optoelectronics
• Chemistry

Background:

• Third-order nonlinear optical (NLO) materials are crucial for advanced photonic devices.
• Molecules with extended π-conjugation and high electronic delocalization exhibit significant NLO properties.
• Metal-organic frameworks (MOFs) offer tunable structures for tailored material functionalities.

Purpose of the Study:

• To investigate the third-order NLO performance of a novel indium-based MOF incorporating NH2 groups and π-conjugated linkers.
• To characterize the structural features contributing to the observed NLO activity.
• To evaluate the potential of this NH2:MOF-In for photonic applications.

Main Methods:

• Synthesis and crystallization of the indium-based metal-organic framework (NH2:MOF-In).
• Structural characterization including crystallographic analysis (diamond topology).
• Measurement of nonlinear optical parameters (nonlinear refractive index, nonlinear absorption coefficient, third-order susceptibility) at 532 nm.

Main Results:

• NH2:MOF-In exhibits enhanced third-order NLO performance due to its π-conjugated linkers, amine functionalities, and stable framework.
• Key NLO parameters determined: nonlinear refractive index (n2) in the range of (0.93-1.32) × 10⁻⁷ cm²/W and nonlinear absorption coefficient (β) of (1.39-3.67) × 10⁻³ cm/W.
• The indium centers and ligand coordination facilitate efficient electron delocalization and enhanced polarizability.

Conclusions:

• NH2:MOF-In demonstrates significant potential as a third-order NLO material.
• The material's structural and electronic properties are well-suited for applications in all-optical switching and high-speed optical data transmission.
• This study highlights MOFs as a promising platform for developing next-generation photonic components.