Electronic phase separation in the slightly underdoped iron pnictide superconductor Ba1-xKxFe2As2.
Here we present a combined study of the slightly underdoped novel pnictide superconductor Ba1-xKxFe2As2 by means of x-ray powder diffraction, neutron scattering, muon-spin rotation (microSR), and magnetic force microscopy (MFM). Static antiferromagnetic order sets in below T{m} approximately 70 K as inferred from the neutron scattering and zero-field-microSR data. Transverse-field microSR below Tc shows a coexistence of magnetically ordered and nonmagnetic states, which is also confirmed by MFM imaging. We explain such coexistence by electronic phase separation into antiferromagnetic and superconducting- or normal-state regions on a lateral scale of several tens of nanometers. Our findings indicate that such mesoscopic phase separation can be considered an intrinsic property of some iron pnictide superconductors.
Park
J T
JT
Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany.
Inosov
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Niedermayer
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Sun
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Haug
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Christensen
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Dinnebier
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Boris
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Drew
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Schulz
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Shapoval
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Wolff
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Neu
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Yang
Xiaoping
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Lin
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Keimer
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Hinkov
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