Critical behavior of sound attenuation in a metamagnetic Ising system

Gulpinar G.

PHYSICS LETTERS A, cilt.372, sa.2, ss.98-105, 2008 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 372 Sayı: 2
  • Basım Tarihi: 2008
  • Doi Numarası: 10.1016/j.physleta.2007.10.037
  • Dergi Adı: PHYSICS LETTERS A
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.98-105
  • Anahtar Kelimeler: metamagnetic Ising system, irreversible thermodynamics, sound attenuation, attenuation peaks, MAGNETIC PHASE TRANSITIONS, SPIN-LATTICE-RELAXATION, ULTRASONIC-ATTENUATION, CRITICAL-POINT, NEEL TEMPERATURE, 1ST SOUND, IRREVERSIBLE-PROCESSES, RECIPROCAL RELATIONS, LIQUID-HELIUM, DISPERSION
  • Dokuz Eylül Üniversitesi Adresli: Evet

Özet

In this study, the sound attenuation coefficient of a spin-1/2 metamagnetic Ising system is calculated by the method of thermodynamics of irreversible processes. The behavior of sound attenuation near the phase transition temperatures is analyzed according to various values of phenomenological rate coefficients (gamma(ij)). For all gamma(m) and gamma(s), values it is found that sound attenuation peaks occur below T-N(H) and depend on frequency omega and the value of the off-diagonal rate coefficient gamma. On the other hand, the critical behavior of the sound attenuation in the hydrodynamic regime is obtained analytically via the critical exponents. Moreover, the behavior of the sound attenuation as a function of frequency is also investigated and omega(2) dependence is observed for the attenuation coefficient. These results are in a good agreement with ultrasonic investigations of magnetic systems. (C) 2007 Elsevier B.V. All rights reserved.