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arXiv · 1310.6071

Large low-temperature magnetoresistance in SrFe2As2 single crystals

S. V. Chong·G. V. M. Williams·J. Kennedy·F. Fang·J. L. Tallon·K. Kadowaki
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Abstract

We present the first report on a large low-temperature magnetoresistance (MR) of more than 1600% in a SrFe2As2 single crystal and 1300% in a low-energy Ca ion-implanted SrFe2As2 single crystal that occurs before the emergence of crystallographic strain-induced bulk superconductivity arising from a sample aging effect. In accordance to band structure calculations from literature, which consitently show more than 2 bands are involved in the transport, we have modeled this large MR at high fields using a 3-carrier scenario rather than solely on quantum linear MR model generally used to explain the MR in iron-pnictides. At and below 20 K the large MR may be due to 3-carrier transport in an inhomogeneous state where there are superconducting and metallic regions.

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S. V. Chong, G. V. M. Williams, J. Kennedy, F. Fang, J. L. Tallon, K. Kadowaki. 2013-10-22. Large low-temperature magnetoresistance in SrFe2As2 single crystals. https://doi.org/10.1209/0295-5075%2F104%2F17002

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