Progress In Electromagnetics Research
ISSN: 1070-4698, E-ISSN: 1559-8985
Home | Search | Notification | Authors | Submission | PIERS Home | EM Academy
Home > Vol. 121 > pp. 159-179


By J. Costa-Quintana and F. Lopez-Aguilar

Full Article PDF (198 KB)

The monopoles are theoretically defined as charges which produce fields whose divergence is, obviously, different from zero. However, the entities which have been experimentally detected in the spin-ices, with mimetic behavior to that of the magnetic monopoles, generate magnetic fields which seem to be compatible with ∇·B = 0. This apparent contradiction can create confusion and therefore it requires explanation. In this paper we have carried out an analysis of the different electromagnetic fields in the spin-ices materials. We clarify the differences between the average fields of standard Maxwell equations with zero divergence even in spin-ices and the non macroscopic fields when there are magnetic monopoles in these materials. We give the molecular or local fields which allow us to determine the molecular polarizability. We combine the extended Clausius-Mossotti equations with the Lorentz-Drude model for obtaining the extended susceptibility and the optical conductivity which can be used for explaining the action of the electromagnetic fields in spin-ices.

J. Costa-Quintana and F. Lopez-Aguilar, "Molecular EM Fields and Dynamical Responses in Solids with Magnetic Charges," Progress In Electromagnetics Research, Vol. 121, 159-179, 2011.

1. Dirac, P. A. M., "Quantized singularities in the electromagnetic field," Proc. Roy. Soc., Vol. A133, 60, 1931.

2. Jordan, P., "The Dirac magnetic pole," Ann. Physik, Vol. 32, 66, 1938.

3. Hooft, G.'t, "Magnetic monopoles in unified gauge theories," Nuclear Physics B, Vol. 79, 276-284, 1974.

4. Polyakov, A. M., "Particle spectrum in quantum field theory," JETP Lett., Vol. 20, 194-195, 1974.

5. Cabrera, B., "First results from a superconductive detector for moving magnetic monopoles," Phys. Rev. Lett., Vol. 48, 1378-1381, 1982.

6. Balestra, S., G. Giacomelli, M. Giorgini, L. Patrizii, V. Popa, Z. Sahnoun, and V. Togo, "Magnetic monopole bibliography-II," arXiv: 1105.5587v1 [hep-ex], May 27, 2011, and references therein.

7. Castelnovo, C., R. Moessner, and S. L. Sondhi, "Magnetic monopoles in spin ice,", (see complementary material published in the same journal where the equivalence between Hamiltonians (1) and (2) is demonstrated), Nature, Vol. 451, 42-45, 2008.

8. Sondhi, S., "Wien route to monopoles," Nature, 888-889, 2009.

9. Qi, X.-L., R. Li, J. Zang, and S.-C. Zhang, "Inducing a magnetic monopole with topological surface states," Science, Vol. 323, 1184-1187, 2009.

10. Morris, D. J. P., D. A. Tennant, S. A. Grigera, B. Klemke, C. Castelnovo, R. Moessner, C. Czternasty, M. Meissner, K. C. Rule, J.-U. Hoffmann, K. Kiefer, S. Gerischer, D. Slobinsky, and R. S. Perry, "Dirac strings and magnetic monopoles in the spin ice Dy2Ti2O7," Science, Vol. 326, 411-414, 2009.

11. Bramwell, S. T., S. R. Giblin, S. Calder, R. Aldus, D. Prabhakaran, and T. Fennell, "Measurement of the charge and current of magnetic monopoles in spin ice," Nature, Vol. 461, 956-960, 2009.

12. Giblin, S. R., S. T. Bramwell, P. C. W. Holdsworth, D. Prabhakaran, and I. Terry, "Creation and measurement of long-lived magnetic monopole currents in spin ice," Nature Phys., Vol. 7, 252-258, 2011.

13. Mol, L. A. S., W. A. Moura-Melo, and A. R. Pereira, "Conditions for the magnetic monopolesin nanoscale squarre arrays of dipolar spin-ice," Phys. Rev. B, Vol. 82, 054434-1-6, 2010.

14. Mellado, P., O. Petrova, Y. Shen, and O. Tchernyshyov, "Dynamics of magnetic charges in artificial spin ice," Phys. Rev. Lett., Vol. 105, 187206-1-4, 2010.

15. Tchernyshyov, O., "No longer on thin ice," Nature Phys., Vol. 6, 323-324, 2010.

16. Umul, Y. Z., "Rigorous expressions for the equivalent edge currents," Progress In Electromagnetics Research B, Vol. 15, 77-94, 2009.

17. Umul, Y. Z., "Electric charges that behave as magnetic monopoles," Progress In Electromagnetics Research Letters, Vol. 18, 19-28, 2010.

18. Quijano, J. L. A. and G. Vecchi, "Field and source equivalence in source reconstruction on 3D surfaces," Progress In Electromagnetics Research, Vol. 103, 67-100, 2010.

19. Ladak, S., D. E. Read, G. K. Perkins, L. F. Cohen, and W. R. Branford, "Direct observation of magnetic monopole defects in an artificial spin-ice system," Nature Phys., Vol. 6, 359-363, 2010.

20. Gingras, M. J., "Observing monopoles in a magnetic analog of ice," Science, Vol. 326, 375-376, 2009.

21. Mengotti, E., L. J. Heyderman, A. F. Rodriguez, F. Nolting, R. V. Hugli, and H.-B. Braun, "Real-space observation of emergent magnetic monopoles and associated Dirac strings in artificial kagome spin ice," Nature Phys., Vol. 7, 68-74, 2011.

22. Bonitz, M., "A plasma of magnetic monopoles," Nature Phys., Vol. 7, 192-194, 2011.

23. Jaubert, L. D. C. and P. C. W. Holsworth, "Signature of magnetic monopole and dirac string dynamics in spin ice," Nature Phys., Vol. 5, 258-261, 2009.

24. Sternberg, N. and A. I. Smolyakov, "Resonant transparency of a three-layer structure containing the dense plasma region," Progress In Electromagnetics Research, Vol. 99, 37-52, 2009.

25. Elliot, R. S., Electromagnetics, McGraw-Hill, 1966.

26. Kittel, C., "Introduction to Solid State Physics," John Wiley & Sons, Inc., 1986.

27. Landau, L. D., E. M. Lifshitz, and L. P. Pitaevskii, "Electrodynamics of Continuous Media," Elsevier, 1993.

28. Jackson, J. D., Classical Electrodynamics, 3rd Ed., John Wiley & Sons, Inc., 1999.

29. Lorrain, P. and D. R. Corson, Electromagnetics Fields and Waves, Freeman, 1988.

30. Cumings, J., "Artifocial ice goes thermal," Nature Phys., Vol. 7, 7-8, 2011.

31. Bramwell, S. T. and M. J. P. Gingras, "Spin ice state in frustrated magnetic pyrochlore materials," Science, Vol. 294, 1495-1501, 2001.

32. Costa-Quintana, J. and F. Lopez-Aguilar, "Extended classical electrodynamics with magnetic monopoles," Far East Journal of Mechanical Engineering and Physics, Vol. 1, 19-56, 2010.

33. Costa-Quintana, J. and F. Lopez-Aguilar, "Propagation of electromagnetic waves in material media with magnetic monopoles," Progress In Electromagnetics Research, Vol. 110, 267-295, 2010.

34. Costa-Quintana, J. and F. López-Aguilar, "Fresnel coeficients in materials with magnetic monopoles," Optics Express, Vol. 19, 3742-3757, 2011.

35. Shnir, Y. M., Magnetic Monopoles, Springer-Verlag, Berlin, 2005.

© Copyright 2014 EMW Publishing. All Rights Reserved