Strong correlations and the search for high-Tc superconductivity in chromium pnictides and chalcogenides

Abstract

Undoped iron superconductors accommodate $n=6$ electrons in five d-orbitals. Experimental and theoretical evidence shows that the strength of correlations increases with hole-doping, as the electronic filling approaches half-filling with $n=5$ electrons. This evidence delineates a scenario in which the parent compound of iron superconductors is the half-filled system, in analogy to cuprate superconductors. In cuprates the superconductivity can be induced upon electron or hole doping. In this work we propose to search for high-Tc superconductivity and strong correlations in chromium pnictides and chalcogenides with $n<5$ electrons. By means of ab-initio, slave spin and multi-orbital RPA calculations we analyse the strength of the correlations and the superconducting and magnetic instabilities in these systems with main focus on LaCrAsO. We find that electron-doped LaCrAsO is a strongly correlated system with competing magnetic interactions, being $(\pi ,\pi )$ antiferromagnetism and nodal d-wave pairing the most plausible magnetic and superconducting instabilities, respectively.

5 pages, 5 figures + supplementary information: 3 pages, 3 figures

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Cited by in corpus (7)

• First principles study of structural, magnetic and electronic properties of CrAs
• Absence of superconductivity in electron-doped chromium pnictides ThCrAsN${}_{1-x}$O${}_x$
• Nematic fluctuations in the non-superconducting iron pnictide BaFe${}_{1.9-x}$Ni${}_{0.1}$Cr${}_x$As${}_2$
• Itinerant G-type antiferromagnet SrCr2As2 studied by magnetization, heat capacity, electrical resistivity, and NMR measurements
• Enhanced Itinerant Ferromagnetism in Hole-doped Transition Metal Oxides: Beyond the Canonical Double Exchange Mechanism
• PhD Thesis: Electronic correlations in multiorbital systems
• Doping-dependent orbital magnetism in Chromium pnictides