Magnets

Whereas the quantitative analysis of critical behaviour during magnetic phase transition in the idealized basic models has been performed by now with a high precision (in fact it constitutes the main contents of the modern phase transition theory), description of criticality at presence of such realistic conditions as the structural disorder, anisotropy, frustrations, finite-size effects is an actual, hard, and interesting problem. This task is actual, because real objects where magnetic phase transitions occur very often are characterized by the substitutional disorder (solid solutions of (anti)ferromagnetic crystals with non-magnetic isomorphes) [1], local random anisotropy (amorphous alloys of the rear-earth elements with transition metals) [2], frustrations (stacked triangular antiferromagnets, helimagnets) [3]. This task is hard, because together with the common problems arising at description of criticality one faces typical problems of the physics of disordered systems. And interest and perspective of studying this task is caused, in particular, by the fact, that due to the universality of critical behaviour, described effects may be observed and are already observed not only in magnetic systems, and, on a larger scale, not only in the condensed matter physics. Some of our results that concern influence of realistic conditions on the peculiarities of ordering in three- and two-dimensional [3] magnets are summarized in papers [1-6].

  1. R. Folk, Yu. Holovatch, T. Yavors'kii. "Critical exponents of a three-dimensional weakly diluted quenched Ising model"   Uspiekhi Fizichieskikh Nauk,  vol. 173 (2003) 175 . [Physics-Uspiekhi, vol. 46 (2003) 169] abstract, ps

  2. M. Dudka, R. Folk, Yu. Holovatch.   "Critical properties of random anisotropy magnets" JMMM, vol. 294 (2005) pp. 305-329. abstract, ps

  3. O. Kapikranian, B. Berche, Yu. Holovatch.   "The 2D XY model on a finite lattice with structural disorder: quasi-long-range ordering under realistic conditions." Eur. Phys. J. B,vol. 56 (2007) 93-105. abstract, pdf

  4. B. Delamotte, Yu. Holovatch, D. Ivaneyko, D. Mouhanna, M. Tissier.   "Fixed points in frustrated magnets revisited." J. Stat. Mech. (2008) P03014. abstract, pdf

  5. D. Ivaneyko, B. Berche, Yu. Holovatch, J. Ilnytskyi.   "On the universality class of the 3d Ising model with long-range-correlated disorder." Physica A, vol. 387 (2008) 4497–4512. abstract, pdf

  6. R. Folk, Yu. Holovatch, G. Moser.   "Field theory of bicritical and tetracritical points. III. Relaxational dynamics including conservation of magnetization (Model C)" Phys. Rev. E, vol. 79 (2009) 031109. abstract, pdf

    Last updated March 12, 2010.