IFLYSIB   05383
INSTITUTO DE FISICA DE LIQUIDOS Y SISTEMAS BIOLOGICOS
Unidad Ejecutora - UE
artículos
Título:
Critical wetting in the two-dimensional Ising ferromagnet confined between inhomogeneous walls
Autor/es:
MARTA L. TROBO; EZEQUIEL V. ALBANO
Revista:
EUROPEAN PHYSICAL JOURNAL B - CONDENSED MATTER
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 2014 vol. 87 p. 1 - 11
ISSN:
1434-6028
Resumen:
&lt;!-- @page { margin: 0.79in } P { margin-bottom: 0.08in } --&gt; We present a numerical study of the critical wetting behavior of an Ising magnet confined between two walls, 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. By considering surface fields varying spatially with a given wavelength or period (λ), H1 (x, λ) with 1 ≤ x ≤ M , we found that the wetting temperature is given by the exact result of Abraham [D.B.Abraham, Phys. Rev. Lett. 44, 1165 (1980)] provided that an effective field given by the spacial average value (Heff ≡ 1/λ ∫ H1 (x, λ)dx > 0) is considered. The above results hold in the low wavelength regime, while for λ → ∞ and a bivaluated surface field (i.e., Hmax for x ≤ M/2, and δHmax for x > M/2, with 0 < δ < 1), one observes two almost independent wetting transitions, both being compatible with Abraham?s exact results corresponding to Hmax and δHmax , respectively. On the other hand, for H1 (x, λ) = 0 but Heff = 0 bulk standard critical behavior results is observed.