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Role of the stability of charge ordering in exchange bias effect in doped manganites.

ABSTRACT: In this work we have carried out an elaborate study on the magnetic properties and investigated the exchange bias phenomena of some charge-ordered (CO) manganites. The detailed study of Sm_1-x Ca _x MnO₃ (x?=?0.5, 0.55, 0.6, 0.65, 0.7) compounds shows that Sm_0.4Ca_0.6MnO₃, which is the most robust charge ordered material studied here, shows significantly large exchange bias field (H_E) as compared to the other compounds. Our experimental results and analysis indicate that T_CO, which reflects the stability of the charge-ordered state, is one of the key parameters for the exchange bias effect. Similar behaviour is found in other rare-earth analogues, viz., La_1-x Ca _x MnO₃ and Pr_1-x Ca _x MnO₃ compounds as well. We also found that with increasing stability of CO states in Sm_1-x Ca _x MnO₃ compounds, H_E enhances due to increase in number and reduction in size of ferromagnetic clusters.

SUBMITTER: Dasgupta P

PROVIDER: S-EPMC5468231 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Role of the stability of charge ordering in exchange bias effect in doped manganites.

Dasgupta Papri P Das Kalipada K Pakhira Santanu S Mazumdar Chandan C Mukherjee S S Mukherjee S S Poddar A A

Scientific reports 20170612 1

In this work we have carried out an elaborate study on the magnetic properties and investigated the exchange bias phenomena of some charge-ordered (CO) manganites. The detailed study of Sm1-x Ca x MnO3 (x = 0.5, 0.55, 0.6, 0.65, 0.7) compounds shows that Sm0.4Ca0.6MnO3, which is the most robust charge ordered material studied here, shows significantly large exchange bias field (HE) as compared to the other compounds. Ou ...[more]

PMID: 28607448

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