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Geometric doppler effect: spin-split dispersion of thermal radiation
Nir Dahan1, Yuri Gorodetski, Kobi Frischwasser
1Micro and Nanooptics Laboratory, Faculty of Mechanical Engineering, and Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Physical Review Letters
|January 15, 2011
Summary
Researchers observed a geometric Doppler effect in thermal radiation, causing spin-split dispersion. This spin-dependent splitting in coupled thermal antennas results from spin-orbit interaction and spatial anisotropy, enabling potential manipulation of light emission.
Area of Science:
- Condensed Matter Physics
- Optics
- Quantum Mechanics
Background:
- The study of thermal radiation properties is crucial for understanding light-matter interactions.
- Spin-orbit interaction is a relativistic effect that couples a particle's spin to its momentum.
- Surface waves and their dynamics play a significant role in nanoscale optical phenomena.
Purpose of the Study:
- To observe and characterize a geometric Doppler effect in thermal radiation.
- To investigate spin-dependent dispersion splitting in a coupled thermal antenna array.
- To explore the potential applications of spin-symmetry breaking in thermal emission.
Main Methods:
- Fabrication of a coupled thermal antenna array structure.
- Measurement of thermal radiation properties, including dispersion relations.
- Analysis of spin-dependent effects arising from surface wave dynamics and local anisotropy.
Main Results:
- Observation of a geometric Doppler effect in thermal radiation.
- Demonstration of spin-split dispersion relation in the thermal emission.
- Attribution of the effect to spin-orbit interaction in a spatially rotating anisotropic structure.
Conclusions:
- The geometric Doppler effect provides a novel mechanism for spin-dependent phenomena in thermal radiation.
- Spin-symmetry breaking in thermal emission can be achieved through engineered structures.
- This observation may lead to new methods for controlling spontaneous and stimulated emission.
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