Universality aspects of layering transitions in ferromagnetic Blume-Capel thin films

YÜKSEL Y., AKINCI Ü.

PHYSICA B-CONDENSED MATTER, cilt.433, ss.96-101, 2014 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 433
  • Basım Tarihi: 2014
  • Doi Numarası: 10.1010/j.physb.2013.10.018
  • Dergi Adı: PHYSICA B-CONDENSED MATTER
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.96-101
  • Anahtar Kelimeler: Crystal field, Effective-field theory, Magnetic thin film, Surface magnetism, PHASE-TRANSITIONS, ISING-MODEL, MONTE-CARLO, CURIE-TEMPERATURE, TRANSVERSE FIELD, ORDERING TEMPERATURE, ULTRATHIN FILMS, SHIFT EXPONENT, FREE-SURFACE, FINITE-SIZE
  • Dokuz Eylül Üniversitesi Adresli: Evet

Özet

Critical phenomena and universality behavior of ferromagnetic thin films described by a spin-1 BlumeCapel Hamiltonian has been examined for various thickness values ranging from 3 to 40 layers. Using effective field theory, we have found that crystal field interactions significantly affects the critical value of surface to bulk ratio of exchange interactions R-c at which the critical temperature becomes independent of film thickness L. Moreover, we have extracted the shift exponent lambda from computed data. Based on the results, we have shown that in the presence of surface exchange enhancement, the system may exhibit a dimensional crossover. We have also found that presence of crystal field interactions does not affect the value of lambda. Hence, a ferromagnetic spin-1/2 thin film is in the same universality class with its spin-1 counterpart. (C) 2013 Elsevier B.V. All rights reserved.