AC susceptibility study of YBCO

Guclu N., Kolemen U.

MATERIALS SCIENCE-POLAND, cilt.29, sa.3, ss.209-215, 2011 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 29 Sayı: 3
  • Basım Tarihi: 2011
  • Doi Numarası: 10.2478/s13536-011-0033-5
  • Dergi Adı: MATERIALS SCIENCE-POLAND
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.209-215
  • Anahtar Kelimeler: YBCO, ac susceptibility, simplified Kim model, activation energy, HARMONIC SUSCEPTIBILITIES, CRITICAL-STATE, FLUX-CREEP, SUPERCONDUCTORS
  • Yozgat Bozok Üniversitesi Adresli: Hayır

Özet

The temperature dependence of ac susceptibility of YBCO bulk samples was measured as a function of ac field amplitude and frequency. Analysis of the temperature dependence of the ac susceptibility near the transition temperature (T (c) ) has been done employing the simplified Kim model. We have obtained an empirical function for the penetration field H (p) = H (alpha) (1-t) (beta) , t = T=T (c) . Best fitting to data was obtained with parameters H (alpha) a parts per thousand 6:2 x 10(3) A/m and beta a parts per thousand 1.50. The experimental value agrees well with the model calculations. In addition, as the frequency increases, the peak temperature (T (p) ) shifts to higher temperature. This effect can be interpreted in terms of flux creep. The field dependence of activation energy obtained from the Arrhenius plots for the frequency (f) and (T (p) ) can be described as U ae (H (ac) )(-beta') with beta' a parts per thousand 0:38 for YBCO.