Magnetotransport and magnetoresistance properties of Pr0.68Ca0.32-xSrxMnO3 (x=0, 0.1, 0.18, 0.26 and 0.32) manganites


İZGİ T., KOLAT V. S. , BAYRİ N., KAYA A., GENÇER H., ATALAY S.

JOURNAL OF OPTOELECTRONICS AND ADVANCED MATERIALS, vol.13, pp.648-655, 2011 (Peer-Reviewed Journal) identifier

  • Publication Type: Article / Article
  • Volume: 13
  • Publication Date: 2011
  • Journal Name: JOURNAL OF OPTOELECTRONICS AND ADVANCED MATERIALS
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.648-655

Abstract

In this study, the magnetotransport and magnetoresistance properties of Pr0.68Ca0.32-xSrxMnO3 (x= 0, 0.1, 0.18, 0.26 and 0.32) compounds were investigated. The system illustrate an evolution from a charge-ordered manganite at x = 0, with an insulating-like resistivity and low magnetization values, towards to a completely ferromagnetic metallic state for x = 0.32. Above the metal-insulator transition temperature T-MI, the resistance curves were fitted to the small polaron popping model. The activation energy (E-a) was found to decrease with increasing Sr content. In the phase separated (PS) state, due to the coexistence of ferromagnetic (FM) metallic and charge order (CO) insulating phases, the magnetoresistance (MR) was found to be maximum. The MR ratio of 6.3x10(8) for the sample x = 0 at 60 K is one of the largest MR change has been reported in manganites. The MR values decreases considerably with increasing Sr content and the activation energy decreases with the increase of Sr content