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Fabrication of Polymer Microspheres for Optical Resonator and Laser Applications
Published on: June 2, 2017
Large second harmonic generation and birefringence from extended octupolar π-conjugated structures.
Danyang Dou1, Bingbing Zhang1,2, Daqing Yang1
1College of Chemistry and Materials Science, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei Research Center of the Basic Discipline of Synthetic Chemistry, Key Laboratory of Chemical Biology of Hebei Province, Hebei University Baoding 071002 China wangy@hbu.edu.cn.
Researchers developed new inorganic-organic hybrid crystals using octupolar structures. These materials exhibit strong nonlinear optical (NLO) properties and birefringence, crucial for optical manipulation applications.
Area of Science:
- Materials Science
- Optics
- Crystallography
Background:
- Nonlinear optical (NLO) and anisotropic light-matter interactions are vital for optical manipulation.
- Balancing second harmonic generation (SHG), birefringence, and bandgap in NLO crystals is challenging.
Purpose of the Study:
- To design and synthesize novel melonate-based inorganic-organic hybrid crystals with enhanced NLO and anisotropic properties.
- To achieve simultaneous large optical nonlinearity and birefringence by employing extended octupolar π-conjugated groups.
Main Methods:
- Synthesis of Rb3[C6N7(NCN)3]·3H2O (I) and Cs3[C6N7(NCN)3]·3H2O (II) crystals.
- Experimental characterization of second harmonic generation (SHG) and birefringence.
- Theoretical calculations to understand the electronic structure and NLO properties.
Main Results:
- Crystals I and II exhibited strong SHG responses (∼9× KH2PO4) and large birefringence (≥0.6@546 nm).
- The synthesized crystals possess a suitable bandgap for visible-UV applications.
- Theoretical analysis revealed that octupolar [C6N7(NCN)3]3- groups contribute to enhanced NLO susceptibilities and polarizability.
Conclusions:
- Octupolar structures with extended π-conjugation are effective for developing advanced NLO and birefringence crystals.
- The melonate-based hybrid crystals represent a promising class of materials for optical applications.
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