NMR Study in the Iron-Selenide Rb0.74Fe1.6Se2: Determination of the Superconducting Phase as Iron Vacancy-Free Rb0.3Fe2Se2

作者：Texier Y^*; Deisenhofer J; Tsurkan V; Loidl A; Inosov D S; Friemel G; Bobroff J

来源：Physical Review Letters, 2012, 108(23): 237002.

DOI：10.1103/PhysRevLett.108.237002

Se-77 and Rb-87 nuclear magnetic resonance (NMR) experiments on Rb-0.Fe-74(1). Se-6(2) reveal clearly distinct spectra originating from a majority antiferromagnetic (AF) and a minority metallic-superconducting (SC) phase. The very narrow NMR line of the SC phase evidences the absence of Fe vacancies and any trace of AF order. The Rb content of the SC phase is deduced from intensity measurements identifying Rb0.3(1)Fe2Se2 as the actual composition of the SC fraction. The resulting estimate of 0.15 electrons/Fe brings this class of superconductors 245 family closer to the other Fe-based superconductor families.

• 出版日期2012-6-8