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The Role of Grain Boundaries in Determining the Transport Properties in Magnetite

David C. Mertens·W. Montfrooij·R. J. McQueeney·M. Yethiraj·J. M. Honig
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Abstract

We present magnetoresistance and Hall-effect measurements on single crystal magnetite Fe3O4 close to the Verwey transition Tv = 123.8 K. We show that the formation of grain boundaries accompanying the reduction in crystal symmetry plays a significant role in the electron scattering mechanism, and that grain boundaries can account for the apparent change in sign of the charge carriers below Tv.

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David C. Mertens, W. Montfrooij, R. J. McQueeney, M. Yethiraj, J. M. Honig. 2004-12-14. The Role of Grain Boundaries in Determining the Transport Properties in Magnetite. https://arxiv.org/abs/cond-mat/0412375

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