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arXiv · 1309.7100

Unusual pressure effects on the superconductivity of indirectly electron-doped (Ba1-xLax)Fe2As2 epitaxial films

Takayoshi Katase·Hikaru Sato·Hidenori Hiramatsu·Toshio Kamiya·Hideo Hosono
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Abstract

Applying an external pressure to indirectly electron-doped 122-type (Ba1-xLax)Fe2As2 epitaxial films enhances the superconducting critical temperature (Tc) up to 30.3 K. Different from the other family compounds, the Tc is enhanced not only in the under-doped region but also in the optimally doped and over-doped regions. Narrowing of the superconducting transition width and an increase in the carrier density take place simultaneously in the whole doping region, except at the heavily over-doped limit. This characteristic is unique to and observed only in (Ba1-xLax)Fe2As2, in which the La doping is stabilized via non-equilibrium growth of the vapor phase epitaxy, among the 122-type iron-based superconductors, AFe2As2 (A = Ba, Sr, and Ca).

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Takayoshi Katase, Hikaru Sato, Hidenori Hiramatsu, Toshio Kamiya, Hideo Hosono. 2013-10-11. Unusual pressure effects on the superconductivity of indirectly electron-doped (Ba1-xLax)Fe2As2 epitaxial films. https://doi.org/10.1103/physrevb.88.140503

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