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Updated: Aug 8, 2026
08:01
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
Giant Magnetic Purcell Effect Induced by High-Order Mie Resonances
Haonan Shi1, Ningning Song1, Anjun Huang2
1State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|August 7, 2026
Summary
Researchers enhanced magnetic dipole emission using titanium dioxide (TiO2) spheres and Mie resonances. This overcomes weak magnetic light-matter coupling, boosting light generation for nanophotonics.
Area of Science:
- Nanophotonics
- Quantum Optics
- Materials Science
Background:
- The Purcell effect enhances light-matter interactions, but magnetic dipole transitions are weak.
- Efficiently enhancing magnetic dipole emission is crucial for advanced light sources.
Purpose of the Study:
- To selectively enhance magnetic dipole emission from Europium (Eu3+) emitters.
- To overcome the limitations of weak magnetic light-matter coupling.
Main Methods:
- Exploiting high-order Mie resonances in low-loss titanium dioxide (TiO2) spheres.
- Utilizing a surface-grafting strategy to position Eu3+ emitters near the TiO2 surface.
- Employing single-particle spectroscopy with a magnetic 32-pole Mie resonance.
Main Results:
- Achieved an ~8.7-fold enhancement in the magnetic dipole transition branching ratio of Eu3+ ions.
- Observed an ~38.1-fold increase in the magnetic dipole decay rate.
- Demonstrated efficient conversion of near-field Purcell enhancement to far-field radiation.
Conclusions:
- High-order Mie resonances in TiO2 spheres effectively enhance magnetic dipole emission.
- This work extends Mie-tronics for light generation and magnetic-field-driven nanophotonic applications.
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