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arXiv · 1304.2205

Spontaneous exchange bias in a nanocomposite of BiFeO$_3$-Bi$_2$Fe$_4$O$_9$

Tuhin Maity·Sudipta Goswami·Dipten Bhattacharya·Gopes C. Das·Saibal Roy
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Abstract

We have observed a large as well as path-dependent spontaneous exchange bias (H$_{SEB}$) ($\sim$30-60 mT) in a nanocomposite of BiFeO$_3$-Bi$_2$Fe$_4$O$_9$ across 5-300 K when it is measured in an unmagnetized state following zero-field cooling and appropriate demagnetization. The path dependency yields a variation in the exchange bias depending on the sign of the starting field and the path followed in tracing the hysteresis loop. The asymmetry thus observed - $\Delta$H$_{SEB}$ - is found to be decreasing nonmonotonically across 5-300 K with a peak around 200 K. The $\Delta$H$_{SEB}$ together with large H$_{SEB}$ could have significant ramification in tuning the exchange bias driven effects and consequent applications.

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Tuhin Maity, Sudipta Goswami, Dipten Bhattacharya, Gopes C. Das, Saibal Roy. 2013-04-08. Spontaneous exchange bias in a nanocomposite of BiFeO$_3$-Bi$_2$Fe$_4$O$_9$. https://doi.org/10.1063/1.4796149

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