Phase separation and stripe patterns in K0.8Fe1.6+xSe2 superconductors

Abstract

Structural investigations on the K0.8Fe1.6+xSe2 superconducting materials have revealed remarkable micro-stripes arising evidently from the phase separation. Two coexisted structural phases can be characterized by modulations of q1 = 1/5[a*+3b*], the antiferromagnetic phase K0.8Fe1.6Se2, and q2 = 1/2[a*+b*], the superconducting phase K0.75Fe2Se2, respectively. These stripe patterns likely result from the anisotropic assembly of superconducting particles along the [110] and [1-10] direction. In addition to the notable stripe structures, a nano-scale phase separation also appears in present superconducting system as clearly observed by high-resolution transmission electron microscopy. Certain notable experimental data obtained in this heterogenous system can be quantitatively explained by the percolation scenario.

15 pages, 6 figures

References in corpus (5)

• A Novel Large Moment Antiferromagnetic Order in K0.8Fe1.6Se2 Superconductor
• The effect of varying Fe-content on transport properties of K intercalated iron selenide KxFe2-ySe2
• 57-Fe Mossbauer study of magnetic ordering in superconducting K_0.85Fe_1.83Se_2.09 single crystals
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Cited by in corpus (1)

• Evolution of precipitate morphology during heat treatment and its implications for the superconductivity in KxFe1.6+ySe2 single crystals