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Detecting transition radiation from a magnetic moment
Igor P Ivanov1, Dmitry V Karlovets
1IFPA, Université de Liège, Allée du 6 Août 17, bâtiment B5a, 4000 Liège, Belgium. igor.ivanov@ulg.ac.be
Physical Review Letters
|July 16, 2013
Summary
Vortex electrons, carrying orbital angular momentum, can experimentally reveal magnetic moment contributions to electromagnetic radiation. This offers a new method for studying radiation physics with measurable asymmetries.
Area of Science:
- Quantum Electrodynamics
- Particle Physics
- Optics and Photonics
Background:
- Electromagnetic radiation emission typically involves particle charges, but magnetic moments and higher multipoles also contribute.
- Experimental evidence for magnetic moment contributions to radiation is scarce, with none observed in polarization radiation.
- Existing methods lack sensitivity to detect subtle magnetic effects in radiation.
Purpose of the Study:
- To propose a novel method for experimentally detecting magnetic moment contributions to electromagnetic radiation.
- To investigate the use of vortex electrons with high orbital angular momentum for this detection.
- To explore the potential of vortex electrons as a new tool in radiation physics.
Main Methods:
- Theoretical analysis of electromagnetic radiation emitted by vortex electrons.
- Focus on transition radiation from vortex electrons interacting with a vacuum-dispersive medium interface.
- Calculation of the magnetic moment contribution relative to spin-induced effects for high orbital angular momentum values.
Main Results:
- The orbital angular momentum-induced magnetic moment contribution (ℓℏω/Ee) is significantly larger than spin-induced effects (ℏω/E) for vortex electrons.
- A left-right angular asymmetry in transition radiation is predicted, directly manifesting the magnetic moment contribution.
- Predicted asymmetry of 0.1%-1% for 300 keV vortex electrons with ℓ=100-1000, achievable with current technology.
Conclusions:
- Vortex electrons provide a viable experimental pathway to observe magnetic moment contributions to radiation.
- The predicted measurable asymmetry validates the proposed method for studying fundamental radiation processes.
- Vortex electrons represent a promising new tool for advancing the field of electromagnetic radiation physics.
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