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Induced Quantized Spin Current in Vacuum
Chong-Sun Chu1, Chun-Hei Leung1
1Department of Physics, National Tsing-Hua University, Hsinchu 30013, Taiwan and Center for Theory and Computation, National Tsing-Hua University, Hsinchu 30013, Taiwan.
Physical Review Letters
|September 24, 2021
Summary
The quantum electrodynamics (QED) vacuum, specifically its electrons, becomes spin-polarized in an external electromagnetic field, creating a vacuum spin current. This effect can be measured using a proposed experiment involving liquid crystals.
Area of Science:
- Quantum electrodynamics (QED)
- Condensed matter physics
- Vacuum physics
Background:
- The quantum vacuum is not empty but filled with virtual particles.
- External electromagnetic fields can influence quantum vacuum properties.
- Spin polarization is a key property of particles.
Purpose of the Study:
- To investigate the effect of external electromagnetic fields on the QED vacuum.
- To demonstrate the spin polarization of the vacuum electrons.
- To propose an experimental method for detecting vacuum spin currents.
Main Methods:
- Theoretical analysis of QED vacuum in external electromagnetic fields.
- Derivation of vacuum spin polarization and spin current.
- Proposal of an experimental setup using nematic liquid crystals.
Main Results:
- The QED vacuum electrons are shown to be spin-polarized by an external EM field.
- This spin polarization manifests as a measurable vacuum spin current.
- The proposed experiment can detect the spin torque from this current.
Conclusions:
- External electromagnetic fields induce a fundamental effect in the QED vacuum.
- The vacuum spin current is a detectable phenomenon with potential applications.
- Nematic liquid crystals offer a viable medium for measuring vacuum spin effects.
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