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Electronic Properties of Fluoride and Half-fluoride Superlattices KZnF3/KAgF3 and SrTiO3/KAgF3.

ABSTRACT: We present the formation of cupratelike electronic structures in KAgF3-related superlattices resulted from the confinement together with structural chemical modification by using the generalized gradient approximation augmented with maximally localized Wannier functions analysis. Strong antiferromagnetic coupling found in bulk KAgF3 is held in purely-fluoride KZnF3/KAgF3. Under 4% in-plane compression strain, its Fermi surface shape breaks away from the edge of electron pocket and resembles that of La2CuO4. While within half-fluoride SrTiO3/KAgF3, out-of-plane electronic reconstruction results in electron doping of AgF2 plane and antiferromagnetic state instability, and the Fermi surface shape presents considerable similarity to that in HgBaCuO4. These results shed light on two dimensional antiferromagnetic precursors of a new Ag(II) family of high-temperature superconductors.

SUBMITTER: Yang X

PROVIDER: S-EPMC4626782 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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