IFLYSIB   05383
INSTITUTO DE FISICA DE LIQUIDOS Y SISTEMAS BIOLOGICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Interface localization-delocalization transitions in confined ferromagnets.
Autor/es:
M. TROBO; EZEQUIEL V ALBANO
Lugar:
KYOTO
Reunión:
Workshop; YITP Workshop: Interface fluctuations and the Kardar-Parisi-Zhang (KPZ) universality class; 2014
Institución organizadora:
Yukawa Institute of Theoretical Physics, KYOTO.
Resumen:
We present a numerical study of the localization-delocalization transition of the interfacebetween magnetic domains of different orientation, in an Ising magnet confined between twowalls separated by a distance L, where short-range inhomogeneous surface magnetic fields act.So, samples are assumed to have a size L×M, L being the width and M the length, respectively.The localization-delocalization transition of the interface becomes a true phase transition whenthe thermodynamic limit ( L → ∞, M → ∞) is properly taken, as it follows from scalingarguments. By considering surface fields varying spatially with a given wavelength or period(), H1(x, ) with 1 ≤ x ≤ M, we found that the wetting temperature is given by the exact resultof Abraham [Phys. Rev. Lett. 44, 1165, (1980)] provided that an effective field given by thespacial average value (Heff ≡ 1 R 0 H1(x, )dx > 0) is considered. The above results hold in thelow wavelength regime, while for → ∞ and a bivaluated surface field (i.e., Hmax for x ≤ M/2,and Hmax for x > M/2, with 0 < < 1), one observes two almost independent wettingtransitions, both being compatible with Abraham?s exact results corresponding to Hmax andHmax, respectively. On the other hand, for H1(x, ) 6= 0 but Heff = 0 bulk standard criticalbehavior results is observed.