Topological magnetoelectric effects in microwave farfield radiation
Abstract
Similar to electromagnetism, described by the Maxwell equations, the physics of magnetoelectric (ME) phenomena deals with the fundamental problem of the relationship between electric and magnetic fields. Despite a formal resemblance between the two notions, they concern effects of different natures. In general, MEcoupling effects manifest in numerous macroscopic phenomena in solids with space and time symmetry breakings. Recently, it was shown that the near fields in the proximity of a small ferrite particle with magneticdipolarmode (MDM) oscillations have the space and time symmetry breakings and the topological properties of these fields are different from the topological properties of the freespace electromagnetic fields. Such MDMoriginated fields—called magnetoelectric (ME) fields—carry both spin and orbital angular momenta. They are characterized by powerflow vortices and nonzero helicity. In this paper, we report on observation of the topological ME effects in farfield microwave radiation based on a small microwave antenna with a MDM ferrite resonator. We show that the microwave farfield radiation can be manifested with a torsion structure where an angle between the electric and magnetic field vectors varies. We discuss the question on observation of the regions of localized ME energy in farfield microwave radiation.
 Authors:
 Microwave Magnetic Laboratory, Department of Electrical and Computer Engineering, Ben Gurion University of the Negev, Beer Sheva (Israel)
 Publication Date:
 OSTI Identifier:
 22597760
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 3; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTENNAS; ELECTRICAL PROPERTIES; ELECTROMAGNETIC FIELDS; ELECTROMAGNETISM; FERRITE; FERRITES; HELICITY; MAGNETIC FIELDS; MAGNETIC PROPERTIES; MAXWELL EQUATIONS; MICROWAVE RADIATION; ORBITAL ANGULAR MOMENTUM; RESONATORS; SPIN; SYMMETRY BREAKING; TOPOLOGY; TORSION; VECTORS
Citation Formats
Berezin, M., Kamenetskii, E. O., and Shavit, R.. Topological magnetoelectric effects in microwave farfield radiation. United States: N. p., 2016.
Web. doi:10.1063/1.4958866.
Berezin, M., Kamenetskii, E. O., & Shavit, R.. Topological magnetoelectric effects in microwave farfield radiation. United States. doi:10.1063/1.4958866.
Berezin, M., Kamenetskii, E. O., and Shavit, R.. 2016.
"Topological magnetoelectric effects in microwave farfield radiation". United States.
doi:10.1063/1.4958866.
@article{osti_22597760,
title = {Topological magnetoelectric effects in microwave farfield radiation},
author = {Berezin, M. and Kamenetskii, E. O. and Shavit, R.},
abstractNote = {Similar to electromagnetism, described by the Maxwell equations, the physics of magnetoelectric (ME) phenomena deals with the fundamental problem of the relationship between electric and magnetic fields. Despite a formal resemblance between the two notions, they concern effects of different natures. In general, MEcoupling effects manifest in numerous macroscopic phenomena in solids with space and time symmetry breakings. Recently, it was shown that the near fields in the proximity of a small ferrite particle with magneticdipolarmode (MDM) oscillations have the space and time symmetry breakings and the topological properties of these fields are different from the topological properties of the freespace electromagnetic fields. Such MDMoriginated fields—called magnetoelectric (ME) fields—carry both spin and orbital angular momenta. They are characterized by powerflow vortices and nonzero helicity. In this paper, we report on observation of the topological ME effects in farfield microwave radiation based on a small microwave antenna with a MDM ferrite resonator. We show that the microwave farfield radiation can be manifested with a torsion structure where an angle between the electric and magnetic field vectors varies. We discuss the question on observation of the regions of localized ME energy in farfield microwave radiation.},
doi = {10.1063/1.4958866},
journal = {Journal of Applied Physics},
number = 3,
volume = 120,
place = {United States},
year = 2016,
month = 7
}

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