Electronic transport and magnetoresistivity of La0.4Bi0.1Ca0.5−xSrxMnO3 (x = 0.1 and 0.2)

• Published in: Bulletin of materials science 2015-09, Vol.38 (5), p.1449-1455
• Main Authors: SUBHASHINI, P, MUNIRATHINAM, B, KRISHNAIAH, M, VENKATESH, R, VENKATESHWARLU, D, GANESAN, V
• Format: Article
• Language: English
• Subjects: Bismuth; Chemistry and Materials Science; Conduction heating; Crystallites; Electrical conduction; Electrical resistivity; Electron transport; Engineering; High temperature; Lanthanum; Low temperature; Magnetic fields; Magnetoresistivity; Materials Science; Transition temperature
• ISSN: 0250-4707; 0973-7669
• DOI: 10.1007/s12034-015-1036-3

Electrical resistivity and magnetoresistive behaviour of bismuth-substituted lanthanum manganites La 0.4 Bi 0.1 Ca 0.5− x Sr x MnO 3 ( x = 0.1 and 0.2) were systematically studied by varying the temperature from 2 to 300 K and the magnetic field up to 12 T. The samples were found to crystallize in rhombohedral structure and their morphology shows near-spherical nanosize crystallites. Charge ordering was observed in both the samples under zero field conditions and corresponding transition temperature T CO was found to decrease with the increase of x . Resistivity measurements with magnetic field also showed suppression of magnetoresistivity (MR) with the increase of x and the maximum MR was found to be 98 and 93% for x = 0.1 and 0.2, respectively, at 10 T. In the high-temperature domain, the electronic transport was observed to be dominated by the variable range hopping mechanism for both the samples, whereas in the low-temperature domain the electrical conduction of x = 0.1 sample was observed to be contributed by various other electron scattering mechanisms.