Solid State Science and Technology, Vol. 17, No 1 (2009) 207-214
ELECTRICAL TRANSPORT PROPERTIES OF La0.67(Sr1-xBax)0.33Mn0.9Ti0.1O3 PEROVSKITE MANGANITE
Z.Zalita1,2, S.A.Halim1, K.P.Lim1, Z.A. Talib1, Z. Hishamuddin1 and C.P. Walter1
1Department of Physics, Faculty of Science,
Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
2School of Applied Physics, Faculty of Science and Technology,
Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia
Influence of Ba doping on the structure and electrical transport properties of polycrystalline La0.67(Sr1-xBax)0.33Mn0.9Ti0.1O3 (0 ≤ x ≤ 1.00) perovskite manganites were studied. The samples synthesized by solid-state reaction method experience a transformation from R-3C rhombohedral to Pm3m cubic structure with the increment of Ba concentration. Temperature dependent resistivity showed that the metal-insulator transition temperature decreases from 117 K to 60 K with increasing Ba content up to x = 0.75. The low temperature resistivity below the metal-insulator transition temperature, Tp was well fitted with the ρ = ρo + ρ2T2 equation indicating the contribution of domain or grain boundary mechanisms and the electron-electron scattering mechanism in the conduction. Contrary to that, in the high temperature insulating regime (T > Tp), the resistivity follows variable range hopping (VRH) and small polaron hopping (SPH) conduction mechanisms.
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