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arXiv · 1103.3560

First-principles Studies for the Hydrogen Doping Effects on Iron-based Superconductors

Hiroki Nakamura·Masahiko Machida
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Abstract

We study hydrogen doping effects in an iron-based superconductor LaFeAsO_(1-y) by using the first-principles calculation and explore the reason why the superconducting transition temperature is remarkably enhanced by the hydrogen doping. The present calculations reveal that a hydrogen cation stably locating close to an iron atom attracts a negatively-charged FeAs layer and results in structural distortion favorable for further high temperature transition. In fact, the lattice constant a averaged over the employed supercell shrinks and then the averaged As-Fe-As angle approaches 109.74 degrees with increasing the hydrogen doping amount. Moreover, the calculations clarify electron doping effects of the solute hydrogen and resultant Fermi-level shift. These insights are useful for design of high transition-temperature iron-based superconductors.

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Hiroki Nakamura, Masahiko Machida. 2011-03-18. First-principles Studies for the Hydrogen Doping Effects on Iron-based Superconductors. https://doi.org/10.1143/jpsj.80.073705

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