Frequency and voltage dependence of dielectric loss of MgB2 composites at different temperatures

Korucu D., Ertekin E., Belenli I., ALTINDAL Ş.

Journal of Superconductivity and Novel Magnetism, cilt.26, sa.6, ss.2165-2170, 2013 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 26 Sayı: 6
  • Basım Tarihi: 2013
  • Doi Numarası: 10.1007/s10948-012-1817-5
  • Dergi Adı: Journal of Superconductivity and Novel Magnetism
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.2165-2170
  • Anahtar Kelimeler: AC conductivity, Dielectric properties, Frequency and voltage dependence, MgB2 composites, Temperature effect
  • Hakkari Üniversitesi Adresli: Evet

Özet

The dielectric loss (ε'') properties of MgB2 composites were investigated by using the conductance-voltage (G/w-V) measurements in the wide frequency and applied bias voltage range at four different temperature levels. Experimental results show that both G/w and ε'' are found strong functions of frequency and applied bias voltage for each temperature level. These changes in G/w and ε'' are considerably high especially at low frequencies and temperatures. The values of ε'' decrease exponentially with increasing frequency until 100 kHz and then become almost constant. Such behavior of G/w and ε'' shows that interfacial polarization is more effective especially at low frequencies. In addition, the current-voltage (I-V) characteristics were also evaluated for 100, 200, and 300 K, and the I-V curves for each temperature show linear behavior. Results indicate that the G/w-V measurements may be a useful tool to characterize the dielectric properties and conductivity of MgB2. © 2012 Springer Science+Business Media New York.