Effect of Substrates on Superconducting Properties of MgB2 Thick Films Fabricated by Spraying Method
Küçük Resim Yok
Tarih
2011
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Springer
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
MgB2 thick films have been prepared on Al2O3, MgO and SrTiO3 ceramic substrates using the spray method with two different heat-treatment cycles, 925 A degrees C with 10 min (Group A) and 610 A degrees C with 24 h (Group B). The structural/microstructural (XRD, SEM) and transport (R-T, MR-T) properties of the films prepared were investigated. XRD analysis showed that the films in Groups A and B consisted mainly of MgB2, but the peaks originating from the substrates were also observed in films fabricated on the Al2O3 substrate. From scanning electron microscopy, it was seen that the surface of MgB2 thick films prepared is not sufficiently homogeneous. Some cracks and heaps with different sizes were observed. The best electrical results were obtained for films in Group A on Al2O3 substrate. The T (c) value for films in Group A was found to be 36.1 K, 36 K and 35 K, for Al2O3, MgO and SrTiO3 substrates, respectively. No superconducting state was reached for films in Group B on the SrTiO3 substrate. In all the films which showed a superconducting state, the magnetic field strongly affected T (c) . A tail in the resistance curves was observed with increasing magnetic field for films in Group A on the MgO and SrTiO3 substrates. At magnetic fields above 1 T for films in Group A on the SrTiO3 substrate and above 2 T for films in Group A on the MgO substrate, the zero-resistance temperature, T (0), was not obtained.
Açıklama
Anahtar Kelimeler
MgB2 thick film, Spraying method, Ceramic substrate
Kaynak
Journal of Superconductivity and Novel Magnetism
WoS Q Değeri
Q4
Scopus Q Değeri
N/A
Cilt
24
Sayı
1-2
