Metal-to-metal transition and heavy-electron state in Nd4Ni3O10-delta | |
Article | |
关键词: CRYSTAL-STRUCTURE; PR; VALENCE; | |
DOI : 10.1103/PhysRevB.101.195142 | |
来源: SCIE |
【 摘 要 】
The trilayer nickelate Nd4Ni3O10-delta was investigated by the measurements of x-ray diffraction, electrical resistivity, magnetic susceptibility, and heat capacity. The crystal structure data suggest a higher Ni valence in the inner perovskitelike layer. At ambient pressure the resistivity shows a jump at 162 K, indicating a metal-to-metal transition (MMT). The MMT is also characterized by a magnetic susceptibility drop, a sharp specific-heat peak, and an isotropic lattice contraction. Below similar to 50 K, a resistivity upturn with log T dependence shows up, accompanied with negative thermal expansion. External hydrostatic pressure suppresses the resistivity jump progressively, coincident with the weakening of the log T behavior. The low-temperature electronic specific-heat coefficient is extracted to be similar to 150 mJ K-2 mol-f.u(-1), equivalent to similar to 50 mJ K-2 mol-Ni-1, indicating an unusual heavy-electron correlated state. The novel heavy-electron state as well as the logarithmic temperature dependence of resistivity is explained in terms of the Ni3+-centered Kondo effect in the inner layer of the (NdNiO3)(3) trilayers.
【 授权许可】
Free