Nanoscale layering of antiferromagnetic and superconducting phases in Rb2Fe4Se5

A. Charnukha; A. Cvitkovic; T. Prokscha; D. Pröpper; N. Ocelic; A. Suter; Z. Salman; E. Morenzoni; J. Deisenhofer; V. Tsurkan; A. Loidl; B. Keimer; A. V. Boris

doi:10.1103/physrevlett.109.017003

arXiv · 1202.5446

Nanoscale layering of antiferromagnetic and superconducting phases in Rb2Fe4Se5

A. Charnukha·A. Cvitkovic·T. Prokscha·D. Pröpper·N. Ocelic·A. Suter·Z. Salman·E. Morenzoni·J. Deisenhofer·V. Tsurkan·A. Loidl·B. Keimer·A. V. Boris

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Abstract

We studied phase separation in a single-crystalline antiferromagnetic superconductor Rb2Fe4Se5 (RFS) using a combination of scattering-type scanning near-field optical microscopy (s-SNOM) and low-energy muon spin rotation (LE-\mu SR). We demonstrate that the antiferromagnetic and superconducting phases segregate into nanometer-thick layers perpendicular to the iron-selenide planes, while the characteristic in-plane size of the metallic domains reaches 10 \mu m. By means of LE-\mu SR we further show that in a 40-nm thick surface layer the ordered antiferromagnetic moment is drastically reduced, while the volume fraction of the paramagnetic phase is significantly enhanced over its bulk value. Self-organization into a quasiregular heterostructure indicates an intimate connection between the modulated superconducting and antiferromagnetic phases.

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A. Charnukha, A. Cvitkovic, T. Prokscha, D. Pröpper, N. Ocelic, A. Suter, Z. Salman, E. Morenzoni, J. Deisenhofer, V. Tsurkan, A. Loidl, B. Keimer, A. V. Boris. 2012-02-24. Nanoscale layering of antiferromagnetic and superconducting phases in Rb2Fe4Se5. https://doi.org/10.1103/physrevlett.109.017003

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