Local Superconductivity in Vanadium Iron Arsenide

Athena S. Sefat; Giang D. Nguyen; David S. Parker; Mingming M. Fu; Qiang Zou; An-Ping Li; Huibo B. Cao; 3 L. Duminda Sanjeewa; Li Li; Z. Gai

doi:10.1103/physrevb.100.104525

arXiv · 1903.03660

Local Superconductivity in Vanadium Iron Arsenide

Athena S. Sefat·Giang D. Nguyen·David S. Parker·Mingming M. Fu·Qiang Zou·An-Ping Li·Huibo B. Cao·3 L. Duminda Sanjeewa·Li Li·Z. Gai

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Abstract

We investigate the chemical substitution of group 5 into BaFe2As2 (122) iron arsenide, in the effort to understand why Fe-site hole doping of this compound (e.g., using group 5 or 6) does not yield bulk superconductivity. We find an increase in c-lattice parameter of the BaFe2As2 with the substitution of V, Nb, or Ta; the reduction in c predicts the lack of bulk superconductivity [1] that is confirmed here through transport and magnetization results. However, our spectroscopy measurements find a coexistence of antiferromagnetic and local superconducting nanoscale regions in V-122, observed for the first time in a transition-metal hole-doped iron arsenide. In BaFe2As2, there is a complex connection between local parameters such as composition and lattice strain, average lattice details, and the emergence of bulk quantum states such as superconductivity and magnetism. [1] L. M. N. Konzen, and A. S. Sefat, J. Phys.: Condens. Matter 29 (2017), 083001.

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Athena S. Sefat, Giang D. Nguyen, David S. Parker, Mingming M. Fu, Qiang Zou, An-Ping Li, Huibo B. Cao, 3 L. Duminda Sanjeewa, Li Li, Z. Gai. 2019-08-30. Local Superconductivity in Vanadium Iron Arsenide. https://doi.org/10.1103/physrevb.100.104525

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