Silver(II) route to unconventional superconductivity

Article

关键词: HIGH-TC SUPERCONDUCTIVITY;    MAGNETIC-STRUCTURE;    CRYSTAL;    DIFLUORIDE;   

DOI  :  10.1103/PhysRevB.105.134519

来源: SCIE

【 摘 要 】

The highly unusual divalent silver in silver difluoride (AgF2) features a nearly square lattice of Ag+2 bridged by fluorides. As a structural and electronic analog of cuprates, its superconducting properties are yet to be examined. Our first-principles electronic structure calculations reveal a striking resemblance between AgF2 and the cuprates. Computed spin susceptibility shows a magnetic instability consistent with the experimentally observed antiferromagnetic transition. A linearized Eliashberg theory in the fluctuation-exchange approximation shows an unconventional singlet d-wave superconducting pairing for bulk AgF2 at an optimal electron doping. The pairing is found to strengthen with decreasing interlayer coupling, highlighting the importance of the quasi two-dimensional nature of the crystal structure. These findings place AgF2 in the category of unconventional high-TC superconductors, and its chemical uniqueness may help shed light on the high-TC phenomena.

【 授权许可】

Free