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Electronic structure of quasi-one-dimensional superconductor K2Cr3As3 from first-principles calculations.

ABSTRACT: The electronic structure of quasi-one-dimensional superconductor K2Cr3As3 is studied through systematic first-principles calculations. The ground state of K2Cr3As3 is paramagnetic. Close to the Fermi level, the Cr-3dz(2), dxy, and d(x(2)-y(2)) orbitals dominate the electronic states, and three bands cross EF to form one 3D Fermi surface sheet and two quasi-1D sheets. The electronic DOS at EF is less than 1/3 of the experimental value, indicating a large electron renormalization factor around EF. Despite of the relatively small atomic numbers, the antisymmetric spin-orbit coupling splitting is sizable (?60?meV) on the 3D Fermi surface sheet as well as on one of the quasi-1D sheets. Finally, the imaginary part of bare electron susceptibility shows large peaks at ?, suggesting the presence of large ferromagnetic spin fluctuation in the compound.

SUBMITTER: Jiang H

PROVIDER: S-EPMC4630611 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Electronic structure of quasi-one-dimensional superconductor K2Cr3As3 from first-principles calculations.

Jiang Hao H Cao Guanghan G Cao Chao C

Scientific reports 20151103

The electronic structure of quasi-one-dimensional superconductor K2Cr3As3 is studied through systematic first-principles calculations. The ground state of K2Cr3As3 is paramagnetic. Close to the Fermi level, the Cr-3dz(2), dxy, and d(x(2)-y(2)) orbitals dominate the electronic states, and three bands cross EF to form one 3D Fermi surface sheet and two quasi-1D sheets. The electronic DOS at EF is less than 1/3 of the experimental value, indicating a large electron renormalization factor around EF. ...[more]

PMID: 26525099

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