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arXiv · 1107.1496

Synthesis, crystal structure and magnetism of beta-Fe1.00(2)Se1.00(3) single crystals

Rongwei Hu·Hechang Lei·Milinda Abeykoon·Emil S. Bozin·Simon J. L. Billinge·J. B. Warren·Theo Siegrist·C. Petrovic
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Abstract

Understanding iron based superconductors requires high quality impurity free single crystals. So far they have been elusive for beta-FeSe and extraction of intrinsic materials properties has been compromised by several magnetic impurity phases. Herein we report synchrotron - clean beta-FeSe superconducting single crystals grown via LiCl/CsCl flux method. Phase purity yields evidence for a defect induced weak ferromagnetism that coexists with superconductivity below Tc. In contrast to Fe1+yTe - based superconductors, our results reveal that the interstitial Fe(2) site is not occupied and that all contribution to density of states at the Fermi level must come from in-plane Fe(1).

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Rongwei Hu, Hechang Lei, Milinda Abeykoon, Emil S. Bozin, Simon J. L. Billinge, J. B. Warren, Theo Siegrist, C. Petrovic. 2011-07-07. Synthesis, crystal structure and magnetism of beta-Fe1.00(2)Se1.00(3) single crystals. https://doi.org/10.1103/physrevb.83.224502

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