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Charge-order-induced directional enhancement of non-diagonal second-order nonlinear optical tensor components
Zuju Ma1, Zehui Fang1, Zhenlong Xie1
1School of Environmental and Materials Engineering, Yantai University, Yantai, 264005, China.
Chemical Communications (Cambridge, England)
|May 26, 2026
Summary
Charge ordering in mixed-valence ions can be chemically tuned to enhance non-diagonal nonlinear optical (NLO) tensor components in crystals. This finding provides a design principle for advanced photonic applications.
Area of Science:
- Solid-state chemistry
- Materials science
- Nonlinear optics
Background:
- Selective enhancement of non-diagonal second-order nonlinear optical (NLO) tensor components is an underexplored area.
- Low-symmetry, non-centrosymmetric crystals are crucial for second-order NLO effects.
Purpose of the Study:
- To demonstrate chemical tuning of selective enhancement of non-diagonal NLO tensor components.
- To establish a design principle for photonic applications based on charge ordering.
Main Methods:
- Utilizing density functional theory (DFT) calculations.
- Investigating charge ordering in mixed-valence ions within low-symmetry crystals.
Main Results:
- Periodic Bi3+/Bi5+ ordering in Ag2BiO3 prevents local inversion symmetry, leading to enhanced non-diagonal NLO tensors.
- Disrupting the charge ordering significantly reduces the d24 NLO coefficient.
Conclusions:
- Charge ordering in mixed-valence ions is a viable strategy for tuning NLO properties.
- The findings establish a new design principle for developing materials with enhanced NLO responses for photonic applications.
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