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arXiv 1111.5176cond-mat.supr-con
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超导FeTe0.65 Se 0.35的微结构磁相

Microstructural magnetic phases in superconducting FeTe0.65Se0.35

A. Wittlin, P. Aleshkevych, H. Przybylinska, D. J. Gawryluk, P. Dluzewski, M. Berkowski, R. Puzniak, M. U. Gutowska, A. Wisniewski

摘要:

在本文中,我们解决了一些悬而未决的问题的性质和作用的铁硫属化物系统FeTe 1-xSex的磁不均匀性和它们的相关性在这个系统中的超导电性。用透射电子显微镜、高角环形暗场扫描透射电子显微镜研究了FeTe_(0.65)Se_(0.35)超导单晶的形貌,用磁化强度、比热和磁共振谱表征了它们的磁性和超导性质。我们的数据表明,存在纳米尺度的六方区域共存的tetraxite主机晶格,一种化学无序显示主机原子在晶格中的非均匀分布,以及数百纳米长的缺铁带。从磁性数据和铁磁共振温度依赖性,我们归因于Fe-Te-Se中的磁性相的Fe 3 O 4夹杂物和六方对称的纳米尺度区域的结构的Fe 7Se 8型。我们的研究结果表明,非均匀分布的主机原子可能是超导Fe-Te-Se硫族化合物的一个内在特征,我们发现了一个令人惊讶的相关性表明,生长速度快的晶体较差的晶体性能是一个更好的超导体。

英文摘要:

In this paper, we address a number of outstanding issues concerning the nature and the role of magnetic inhomogenities in the iron chalcogenide system FeTe1-xSex and their correlation with superconductivity in this system. We report morphology of superconducting single crystals of FeTe0.65Se0.35 studied with transmission electron microscopy, high angle annular dark field scanning transmission electron microscopy and their magnetic and superconducting properties characterized with magnetization, specific heat and magnetic resonance spectroscopy. Our data demonstrate a presence of nanometre scale hexagonal regions coexisting with tetragonal host lattice, a chemical disorder demonstrating non homogeneous distribution of host atoms in the crystal lattice, as well as hundreds-of-nanometres-long iron-deficient bands. From magnetic data and ferromagnetic resonance temperature dependence, we attribute magnetic phases in Fe-Te-Se to Fe3O4 inclusions and to hexagonal symmetry nanometre scale regions with structure of Fe7Se8 type. Our results suggest that nonhomogeneous distribution of host atoms might be an intrinsic feature of superconducting Fe-Te-Se chalcogenides and we find a surprising correlation indicating that faster grown crystal of inferior crystallographic properties is a better superconductor.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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