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arXiv · 1012.0616

Magnetic and electrical properties and carrier doping effects on the Fe-based host compound Sr4Sc2Fe2As2O6

S. B. Zhang·Y. F. Guo·Y. G. Shi·S. Yu·J. J. Li·X. X. Wang·M. Arai·K. Yamaura·E. Takayama-Muromachi
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Abstract

Additional charge carriers were introduced to the iron oxyarsenide Sr4Sc2Fe2As2O6 under a high-pressure condition, followed by measurements of electrical resistivity, Hall coefficient, and magnetic susceptibility. The host compound Sr4Sc2Fe2As2O6 shows metallic conductivity down to ~200 K and turns to show a semiconducting-like conductivity accompanied by a positive magneto-resistance (22% at 70 kOe). Although the carrier density is comparable at 300 K (5.9x1021 cm-3) with that of the other Fe-based superconductors, no superconductivity appears down to 2 K. This is primarily because the net carrier density decreases over 3 orders of magnitude on cooling and additionally a possible magnetic order at ~120 K prevents carriers from pairing. The properties were altered largely by introducing the additional carriers.

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S. B. Zhang, Y. F. Guo, Y. G. Shi, S. Yu, J. J. Li, X. X. Wang, M. Arai, K. Yamaura, E. Takayama-Muromachi. 2010-12-03. Magnetic and electrical properties and carrier doping effects on the Fe-based host compound Sr4Sc2Fe2As2O6. https://doi.org/10.1103/physrevb.83.024505

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