Europhys. Lett.
Volume 65, Number 2, January 2004
Page(s) 269 - 275
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 01 January 2004
Europhys. Lett., 65 (2) , pp. 269-275 (2004)
DOI: 10.1209/epl/i2002-10001-5

The anapole moments in disk-form MS-wave ferrite particles

E. O. Kamenetskii

Department of Electrical and Computer Engineering Ben Gurion University of the Negev - Beer Sheva, 84105, Israel

(Received 2 December 2002; accepted 6 November 2003)

The anapole moments describe the parity-violating parity-odd, time-reversal-even couplings between elementary particles and the electromagnetic (EM) field. Surprisingly, anapole-like moment properties can be found in certain artificially engineered physical systems. In microwaves, ferrite resonators with multi-resonance magnetostatic-wave (MS-wave) oscillations may have sizes 2-4 orders less than the free-space EM wavelength at the same frequency. MS-wave oscillations in a ferrite sample occupy a special place between the "pure" electromagnetic and spin-wave (exchange) processes. The energy density of MS-wave oscillations is not the electromagnetic-wave density of energy and not the exchange energy density. These "microscopic" oscillating objects -the particles- may interact with the external EM fields in a very specific way. To describe such interactions, a mathematical apparatus similar to that of the quantum-mechanical analysis should be used. Because of surface magnetic currents, MS oscillations in ferrite disk resonators become parity violating. The parity-violating couplings between disk-form ferrite particles and the external EM field should be analyzed based on the notion of anapole moment.

76.50.+g - Ferromagnetic, antiferromagnetic, and ferrimagnetic resonances; spin-wave resonance.
11.30.Er - Charge conjugation, parity, time reversal, and other discrete symmetries.
03.65.-w - Quantum mechanics.

© EDP Sciences 2004