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Suppressing Energy Migration via Antiparallel Spin Alignment in One-Dimensional Mn2+ Halide Magnets with High
Xinglu Zhu1, Xiaohui Yan2, Enze Kang3
1State Key Laboratory of Luminescent Materials and Devices, and Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510641, China.
Angewandte Chemie (International Ed. in English)
|October 8, 2024
Summary
Antiparallel spin alignment in manganese (Mn2+) chains suppresses energy migration, reducing luminescence quenching. This discovery enhances photoluminescence quantum yield (PLQY) in Mn2+ materials for optoelectronic applications.
Area of Science:
- Materials Science
- Solid-State Physics
- Quantum Chemistry
Background:
- Photoexcited energy migration causes luminescence quenching in Mn2+ materials, hindering optoelectronic applications.
- The role of spin alignment in Mn2+ energy migration and luminescence quenching is largely unexplored.
Purpose of the Study:
- To elucidate the influence of spin alignment on energy migration in Mn2+-metal halide compounds.
- To investigate how spin order affects photoluminescence and energy dynamics in (CH3)4NMnCl3 (TMMC).
Main Methods:
- Variable-temperature photoluminescence (PL) spectroscopy.
- Magnetic-optical spectroscopy.
- Analysis of temperature-dependent magnetic susceptibility and emission peak shifts.
Main Results:
- Demonstrated spin order in TMMC below 55 K via magnetic susceptibility transitions.
- Observed negligible emission peak shifts due to magnetic saturation, confirming spin order.
- Showcased that antiparallel spin alignment in TMMC suppresses energy migration and multiphonon relaxation, reducing nonradiative transitions.
Conclusions:
- Antiparallel spin alignment is a key factor in suppressing energy migration and enhancing photoluminescence quantum yield (PLQY) in Mn2+ materials.
- This finding offers a new strategy for developing high-performance Mn2+-doped phosphors for optoelectronics and spin-photonics.
- Insights into spin and energy dynamics provide pathways for material design and performance optimization.
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