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Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
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Balanced infrared nonlinear optical performance achieved by modulating the covalency and ionicity distributions in
Bin-Wen Liu1, Xiao-Ming Jiang1, Shao-Min Pei1
1State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China. xmjiang@fjirsm.ac.cn.
Materials Horizons
|October 22, 2021
Summary
Researchers developed new infrared nonlinear optical (NLO) materials by finely mixing covalency and ionicity. These materials demonstrate excellent NLO efficiency and high laser-induced damage thresholds (LIDT), offering a new design strategy.
Area of Science:
- Materials Science
- Optics
- Solid State Chemistry
Background:
- Nonlinear optical (NLO) efficiency and laser-induced damage threshold (LIDT) are critical parameters for infrared (IR) NLO materials.
- Balancing NLO efficiency and LIDT is challenging due to the opposing roles of covalency and ionicity.
Purpose of the Study:
- To explore the relationship between the topological features of the electron localization function (ELF) map and the performance of NLO materials.
- To develop a new strategy for designing IR NLO materials with balanced NLO efficiency and LIDT.
Main Methods:
- Evaluation of the fractal dimension of ELF maps for various NLO materials.
- Synthesis of new IR NLO sulfides by introducing chemical bonds with different interaction strengths.
- Characterization of NLO efficiency and LIDT for the synthesized materials.
Main Results:
- A correlation was found between the fine mixing of covalency and ionicity, indicated by ELF topology, and improved NLO performance.
- Three new IR NLO sulfides (A2Ba3Li6Ga28S49, A = K, Rb, Cs) were successfully synthesized.
- The new materials exhibit strong NLO efficiency and high LIDTs, outperforming established benchmarks like AgGaS2.
Conclusions:
- The topological features of the ELF map can serve as a guide for designing high-performance IR NLO materials.
- Simultaneous introduction of chemical bonds with varying strengths is an effective method for achieving fine mixing of covalency and ionicity.
- The synthesized sulfides are promising candidates for advanced IR NLO applications.
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