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arXiv · 0902.2240

Growth and Superconductivity of FeSex Crystals

U. Patel·J. Hua·S. H. Yu·S. Avci·Z. L. Xiao·H. Claus·J. Schlueter·V. V. Vlasko-Vlasov·U. Welp·W. K. Kwok
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Abstract

Iron selenide (FeSex) crystals with lateral dimensions up to millimeters were grown via a vapor self-transport method. The crystals consist of the dominant alpha - phase with trace amounts of beta- phase as identified by powder x-ray diffraction. With four-probe resistance measurements we obtained a zero-resistance critical temperature of 7.5 K and a superconducting onset transition temperature of up to 11.8 K in zero magnetic field as well as an anisotropy of 1.5 +- 0.1 for the critical field. Magnetization measurements on individual crystals reveal the co-existence of superconductivity and ferromagnetism.

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U. Patel, J. Hua, S. H. Yu, S. Avci, Z. L. Xiao, H. Claus, J. Schlueter, V. V. Vlasko-Vlasov, U. Welp, W. K. Kwok. 2009-02-13. Growth and Superconductivity of FeSex Crystals. https://doi.org/10.1063/1.3093838

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