Le equazioni di evoluzione dei continui ferromagnetici

P. Podio-Guidugli

Bollettino dell'Unione Matematica Italiana (2001)

  • Volume: 4-B, Issue: 1, page 31-44
  • ISSN: 0392-4041

Abstract

top
This expository paper is meant to be a faithful account the invited lecture I gave in Naples on September 14, 1999, during the 16th Congress of U.M.I., the Italian Mathematical Union. In Section 2, I consider the Gilbert equation, the parabolic equation that rules the evolution of the magnetization vector in a rigid ferromagnet. Among the issues I here discuss are the relations of the Gilbert equation to the harmonic map equation and its heat flow, the existence of global-in-time weak solutions, and some conjectures on the possible evolutions of singular solutions. Section 3 consists of an abridged presentation of dynamical micromagnetics, a general mathematical model for the dynamics of ferromagnetic bodies undergoing arbitrarily large deformations. In particular, I show how a generalized Gilbert equation can be arrived at, and I briefly discuss equilibria and dissipation mechanisms.

How to cite

top

Podio-Guidugli, P.. "Le equazioni di evoluzione dei continui ferromagnetici." Bollettino dell'Unione Matematica Italiana 4-B.1 (2001): 31-44. <http://eudml.org/doc/194812>.

@article{Podio2001,
author = {Podio-Guidugli, P.},
journal = {Bollettino dell'Unione Matematica Italiana},
keywords = {Gilbert equation; parabolic equation; magnetization vector; harmonic map equation; existence; weak solutions},
language = {ita},
month = {2},
number = {1},
pages = {31-44},
publisher = {Unione Matematica Italiana},
title = {Le equazioni di evoluzione dei continui ferromagnetici},
url = {http://eudml.org/doc/194812},
volume = {4-B},
year = {2001},
}

TY - JOUR
AU - Podio-Guidugli, P.
TI - Le equazioni di evoluzione dei continui ferromagnetici
JO - Bollettino dell'Unione Matematica Italiana
DA - 2001/2//
PB - Unione Matematica Italiana
VL - 4-B
IS - 1
SP - 31
EP - 44
LA - ita
KW - Gilbert equation; parabolic equation; magnetization vector; harmonic map equation; existence; weak solutions
UR - http://eudml.org/doc/194812
ER -

References

top
  1. ALOUGES, F.- SOYEUR, A., On global weak solutions for Landau-Lifshitz equations:existence and nonuniqueness, Nonlinear Anal. Theory, Meth. Appl., 18 (1992), 1071. Zbl0788.35065MR1167422
  2. BARYAKTHAR, V. G.- IVANOV, B. A.- SUKSTANSKII, A. L.- MELIKHOV, E. YU., Soliton relaxation in magnets, Phys. Rev. B, 56 (1997), 619. 
  3. BERTSCH, M.- DAL PASSO, R.- VAN DER HOUT, R., Nonuniqueness for the heat flow ofharmonic maps on the disk, Quad. I.A.C.-C.N.R. 9/1999. Zbl1006.35050
  4. BERTSCH, M.- PODIO-GUIDUGLI, P.- VALENTE, V., On the dynamics of deformable ferromagnets. I. Global weak solutions for soft ferromagnets at rest. I.A.C. Quad.1/1999, in corso di stampa su Annali Mat. Pura Appl. Zbl1097.74017
  5. BETHUEL, F.- CORON, J.-M.- GHIDAGLIA, J. M.- SOYEUR, A., Heat flows and relaxedenergies for harmonic maps, In Nonlinear Diffusion Equations and their Equilibrium States, Gregynog, Birkhäuser (1990). Zbl0795.35053
  6. BREZIS, H.- CORON, J.-M.- LIEB, E. H., Harmonic maps with defects, Comm. Math.Phys., 107 (1986), 649. Zbl0608.58016MR868739
  7. BROWN, W. F., MAGNETOELASTIC INTERACTIONS, SPRINGER-VERLAG (1966). 
  8. BROWN, W. F., MICROMAGNETICS, KRIEGER, 1978. 
  9. CHANG, K.-C.- DING, W.-Y.- YE, R., Finite-time blow-up of the heat flow of harmonicmaps from surfaces, J. Differential Geometry, 36 (1992), 507. Zbl0765.53026MR1180392
  10. CHEN, Y.- STRUWE, M., Existence and partial regularity results for the heat flow forharmonic maps, Math. Z., 201 (1989), 83. Zbl0652.58024MR990191
  11. CORON, J.-M., Nonuniqueness for the heat flow of harmonic maps. Ann. Inst. Henri Poincaré, 7 (1990), 335. Zbl0707.58017MR1067779
  12. DE SIMONE, A.- PODIO-GUIDUGLI, P., Inertial and self interactions in structured continua: liquid crystals and magnetostrictive solids, MECCANICA, 30 (1995), 629. Zbl0835.73060MR1360976
  13. DE SIMONE, A.- PODIO-GUIDUGLI, P., On the continuum theory of deformable ferromagnetic solids, Arch. Rational Mech. Anal., 136 (1996), 201. Zbl1002.74521MR1423008
  14. DE SIMONE, A.- PODIO-GUIDUGLI, P., Pointwise balances and the construction of stress fields in dielectrics, Math. Models & Methods Appl. Sci., 7 (1997), 477. Zbl0889.73060
  15. FREIRE, A., Uniqueness for the harmonic map flow from surfaces to general targets, Comment. Math. Helv., 70 (1995), 310. Zbl0831.58018MR1324632
  16. GILBERT, T. L., A Lagrangian formulation of the gyromagnetic equation of the magnetization field, Phys. Rev., 100 (1955) 1243. 
  17. HARDT, R. M., Singularities of harmonic maps, Bull. Amer. Math. Soc., 34 (1997), 15. Zbl0871.58026MR1397098
  18. HONG, M.-C., Some new examples for nonuniqueness of the evolution problem of harmonic maps, Comm. Anal. Geom., 6 (1998), 779. Zbl0949.58016MR1664892
  19. LANDAU, L.- LIFSHITZ, E., On the theory of the dispersion of magnetic permeability in ferromagnetic bodies, Phys. Z. Sowjet., 8 (1935), 153. Ristampato alle pp. 101-114 di «Collected Papers of L.D. Landau», D.ter Haar Ed., Pergamon Press (1965). Zbl0012.28501
  20. PODIO-GUIDUGLI, P., Inertia and invariance, Ann. Mat. Pura Appl., 172 (1997),103-124. Zbl0949.74003MR1621147
  21. PODIO-GUIDUGLI, P., On dissipation mechanisms in micromagnetics, inviato per la pubbl. (2000). 
  22. PODIO-GUIDUGLI, P.- VALENTE, V., Existence of global weak solutions to a modified Landau-Lifshitz equation, in preparazione (1999). 
  23. STRUWE, M., Geometric evolution problems of «Nonlinear Partial Differential Equations in Differential Geometry», IAS Park City Math. Ser., Vol. 2, Am. Math. Soc. (1996), 257. Zbl0847.58012MR1369591
  24. VISINTIN, A., On Landau-Lifshitz' equations for ferromagnetism, Japan J. Appl. Math., 2 (1985), 69. Zbl0613.35018MR839320
  25. VISINTIN, A., Modified Landau-Lifshitz equation for ferromagnetism, Physica B, 233 (1997), 365. Zbl0613.35018

NotesEmbed ?

top

You must be logged in to post comments.

To embed these notes on your page include the following JavaScript code on your page where you want the notes to appear.

Only the controls for the widget will be shown in your chosen language. Notes will be shown in their authored language.

Tells the widget how many notes to show per page. You can cycle through additional notes using the next and previous controls.

    
                

Note: Best practice suggests putting the JavaScript code just before the closing </body> tag.