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arXiv · 1004.0659

Electron-hole asymmetry in Co- and Mn-doped SrFe2As2

J. S. Kim·Seunghyun Khim·H. J. Kim·M. J. Eom·J. Law·R. K. Kremer·Ji Hoon Shim·Kee Hoon Kim
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Abstract

Phase diagram of electron and hole-doped SrFe2As2 single crystals is investigated using Co and Mn substitution at the Fe-sites. We found that the spin-density-wave state is suppressed by both dopants, but the superconducting phase appears only for Co (electron)-doping, not for Mn (hole)-doping. Absence of the superconductivity by Mn-doping is in sharp contrast to the hole-doped system with K-substitution at the Sr sites. Distinct structural change, in particular the increase of the Fe-As distance by Mn-doping is important to have a magnetic and semiconducting ground state as confirmed by first principles calculations. The absence of electron-hole symmetry in the Fe-site-doped SrFe2As2 suggests that the occurrence of high-Tc superconductivity is sensitive to the structural modification rather than the charge doping.

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J. S. Kim, Seunghyun Khim, H. J. Kim, M. J. Eom, J. Law, R. K. Kremer, Ji Hoon Shim, Kee Hoon Kim. 2010-04-05. Electron-hole asymmetry in Co- and Mn-doped SrFe2As2. https://doi.org/10.1103/physrevb.82.024510

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