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Updated: Jun 17, 2025
08:01
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
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Magneto-optical Particles in Isotropic Spinning Fields Mimic Magnetic Monopoles
Manuel I Marqués1, Shulamit Edelstein2, Pedro A Serena2
1Departamento de Física de Materiales, <a href="https://ror.org/01cby8j38">Universidad Autónoma de Madrid</a>, 28049 Madrid, Spain; Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain; and Instituto Nicolás Cabrera (INC), Universidad Autónoma de Madrid, 28049 Madrid, Spain.
Physical Review Letters
|August 9, 2024
Summary
Researchers demonstrate a novel method to propel particles using a spinning magnetic field and magneto-optical effects, mimicking magnetic monopoles. This nonreciprocal phenomenon offers new possibilities in condensed matter physics and optical manipulation.
Area of Science:
- Condensed matter physics
- Optics
- Electromagnetism
Background:
- Typical electric currents are driven by Coulombic forces.
- Few condensed matter systems exhibit particle forces proportional to constant magnetic fields.
Purpose of the Study:
- To present a novel method for particle propulsion using magnetic fields.
- To explore a purely nonreciprocal effect based on isotropic radiation spinning fields and magneto-optical interactions.
Main Methods:
- Utilizing an isotropic radiation spinning field.
- Leveraging the magneto-optical effect in condensed matter.
- Investigating the induced "magnetic charge" and optical torque.
Main Results:
- Particles are propelled by a magnetic field, analogous to magnetic monopoles.
- The induced "magnetic charge" is linearly dependent on the field's helicity.
- A purely nonreciprocal effect is demonstrated, distinct from reciprocal chiral dipoles.
Conclusions:
- The study introduces an artificial magnetic monopole behavior in condensed matter.
- This effect is driven by light-matter interactions and helicity.
- The artificial monopole exhibits optical torque and no interaction with external electric fields.
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