On the temperature dependence of the sound attenuation maximum as a function of frequency and magnetic field in a spin-1 Ising model near the critical region

Erdem R., Keskin M.

PHYSICS LETTERS A, cilt.326, sa.1-2, ss.27-31, 2004 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 326 Sayı: 1-2
  • Basım Tarihi: 2004
  • Doi Numarası: 10.1016/j.physleta.2004.04.030
  • Dergi Adı: PHYSICS LETTERS A
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.27-31
  • Anahtar Kelimeler: spin-1 Ising model, sound attenuation maximum, temperature dependence, Onsager theory, PHASE-TRANSITION POINT, ULTRASONIC-ATTENUATION, RELAXATION PHENOMENA, NEEL TEMPERATURE, LATTICE-RELAXATION, SYSTEM, PROPAGATION, MNF2, BEHAVIOR, RBMNF3
  • Akdeniz Üniversitesi Adresli: Hayır

Özet

Using the lowest approximation of the cluster variation method and Onsager theory, calculations of the sound attenuation (alpha) near the critical point in a spin-1 Ising model were performed at different frequencies (omega) and different magnetic field values (H) simultaneously and the shift in temperature of the attenuation maximum (DeltaT) was detected. It is found that the attenuation 'peaked' at higher temperatures with decreasing frequency and increasing field values, obeying an approximately exponential function in omega-DeltaT plots and linear function in H-DeltaT plots. 'Closed loops' are also observed in the alpha-alpha plots. These results are in qualitative agreement with the measurements of the ultrasound attenuation near the Neel point in magnetic insulators. (C) 2004, Elsevier B.V. All rights reserved.