Archimedean solid-like superconducting framework in phase-separated K0.8Fe1.6+xSe2 (0<=x<=0.15)

Abstract

The superconducting (SC) phase in the phase-separated (PS) K0.8Fe1.6+xSe2 (0<=x<=0.15) materials is found to crystallize on Archimedean solid-like frameworks, this structural feature originate from a spinodal phase separation (SPS) at around Ts~540K depending slightly on the Fe concentration. Two stable phases in K0.8Fe1.6+xSe2 are demonstrated to be the SC K0.5Fe2Se2 and antiferromagnetic (AFM) K0.8Fe1.6Se2. The spinodal waves go along the systematic [113] direction and result in notable lamellar structure as illustrated by using the strain-field theoretical simulation. The 3-dimentional SC framework is constructed by hollow truncated octahedra similar with what discussed for Archimedean solids. Based on this structural model, we can efficiently calculate the volume fraction of SC phase in this type of PS SC materials.

14 pages, 4 figures + Suppl. material (7 pages, 7 figures)

References in corpus (5)

• Intrinsic phase separation in superconducting K0.8Fe1.6Se2 (Tc= 31.8 K) single crystals
• NMR Study in the Iron-Selenide Rb0.74Fe1.6Se2: Determination of the Superconducting Phase as Iron Vacancy-Free Rb0.3Fe2Se2
• Transport properties and anisotropy of Rb0.8Fe2Se2 single crystals
• Evolution of precipitate morphology during heat treatment and its implications for the superconductivity in KxFe1.6+ySe2 single crystals
• Metastable superconducting state in quenched KxFe2-ySe2

Cited by in corpus (8)

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• Role of the Extra-Fe in K2-xFe4+ySe5 superconductors
• Direct Observation of Microstructures on Superconducting Single Crystals of K${}_x$Fe${}_{2-y}$Se${}_2$
• Phase-separation control of K${}_x$Fe${}_{2-y}$Se${}_2$ superconductor through rapid-quenching process
• Quenching Dependence on Superconductivity in the Synthesizing Process of Single Crystals of Rb${}_x$Fe${}_{2-y}$Se${}_2$
• In situ observation of phase separation and hierarchical microstructure of KxFe2-ySe2 single crystals