Related Experiment Video
Updated: Jun 14, 2025
07:39
Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
6.8K
Plasmonic Radiation from Spin-Momentum Locking
Yu-Lu Lei1,2, Juan-Feng Zhu3, Zi-Wen Zhang1,2
1Center for Carbon-based Electronics, School of Electronics, Peking University, Beijing, 100871, China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|September 2, 2024
Summary
Researchers generated pure, tunable chiral free-electron radiation by leveraging spin-momentum locking in spoof surface plasmons. This breakthrough overcomes challenges in producing broadband chiral light for advanced applications.
Area of Science:
- Optics and Photonics
- Quantum Information Science
- Materials Science
Background:
- Chiral light emission is crucial for applications like sensing and quantum communication.
- Current methods face challenges in achieving pure, tunable, broadband chiral emission.
- Free-electron radiation offers a potential solution for overcoming these limitations.
Purpose of the Study:
- To present a novel method for generating chiral free-electron radiation.
- To exploit the spin-momentum locking (SML) property of spoof surface plasmons (SSPs) for chiral emission.
- To achieve pure, tunable, and broadband chiral free-electron radiation.
Main Methods:
- Excitation of SSPs by matching free electron phase velocity.
- Transformation of confined SSPs into free-space radiation via wavenumber compensation.
- Conversion of transverse spin angular momentum to longitudinal spin angular momentum via angular momentum conservation.
Main Results:
- Successful generation of pure and tunable chiral free-electron radiation.
- Broad spectrum emission achieved.
- Optimal degree of circular polarization approaching -1 demonstrated.
Conclusions:
- The presented method effectively produces chiral free-electron radiation.
- The technique leverages SML and SSPs for efficient chiral light generation.
- This approach offers new possibilities for chiral emission in various platforms.
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