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arXiv · 1009.4911

Control of Correlations in Sr4V2O6Fe2As2 by Chemical Stoichiometry

Athena S. Sefat·David J. Singh·V. Ovidiu Garlea·Yuri L. Zuev·Michael A. McGuire·Lindsay VanBebber·Brian C. Sales
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Abstract

We show using a combination of powder X-ray and neutron diffraction, first principles calculations, temperature- and field-dependent magnetization, heat capacity and resistivity data that the superconducting behavior of `Sr$_4$V$_2$O$_6$Fe$_2$As$_2$' is dependent on synthesis conditions, particularly, heating profiles result in unintentional chemical doping. This compound can be tuned from a state in which the vanadium electrons are itinerant with a high electronic density of states, to a state where the vanadium-oxide layers are insulating and presumably antiferromagnetic.

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Athena S. Sefat, David J. Singh, V. Ovidiu Garlea, Yuri L. Zuev, Michael A. McGuire, Lindsay VanBebber, Brian C. Sales. 2010-09-24. Control of Correlations in Sr4V2O6Fe2As2 by Chemical Stoichiometry. https://arxiv.org/abs/1009.4911

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