Static quadrupolar susceptibility for a Blume-Emery-Griffiths model based on the mean-field approximation

PAWLAK A., GÜLPINAR G., ERDEM R., Agartioglu M.

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, cilt.395, ss.1-6, 2015 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 395
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1016/j.jmmm.2015.07.024
  • Dergi Adı: JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1-6
  • Anahtar Kelimeler: Blume-Emery-Griffiths model, Multicritical phase diagram, Phase transitions and critical phenomena, Quadrupolar susceptibility, ANTIFERROMAGNETIC POTTS-MODEL, MULTICRITICAL PHASE-DIAGRAMS, RENORMALIZATION-GROUP, MAGNETIC-PROPERTIES, 2 DIMENSIONS, ISING-MODEL, ALLOYS, TRANSITION, BEHAVIOR, DIPOLAR
  • Akdeniz Üniversitesi Adresli: Evet

Özet

The expressions for the dipolar and quadrupolar susceptibilities are obtained within the mean-held approximation in the Blume-Emery-Griffiths model. Temperature as well as crystal held dependences of the susceptibilities are investigated for two different phase diagram topologies which take place for K/J=3 and K/J=5.0.Their behavior near the second and first order transition points as well as multi-critical points such as tricritical, triple and critical endpoint is presented It is found that in addition to the jumps connected with the phase transitions there are broad peaks in the quadrupolar susceptibility. It is indicated that these broad peaks lie on a prolongation of the first-order line from a triple point to a critical point ending the line of first-order transitions between two distinct paramagnetic phases It is argued that the broad peaks are a reminiscence of very strong quaclrupolar fluctuations at the critical point. The results reveal the fact that near ferromagnetic-paramagnetic phase transitions the quaclrupolar susceptibility generally shows a jump whereas near the phase transition between two distinct paramagnetic phases it is an edge-like. (C) 2015 Elsevier BM. All rights reserved,