Relation between susceptibility and Knight shift in La2NiO4.17 and K2NiF4 by 61Ni NMR

摘要: The NiO4 plaquettes in La2NiO4.17, a cousin of the hole-doped high-temperature superconductor La2-xSrxCuO4, have been studied by Ni-61 NMR 14 T single crystal enriched Ni-61. Doped and undoped are discriminated shift resonance, leading to small line splitting, which hardly depends on temperature or susceptibility. smallness effect is additional evidence for location holes as deduced Schussler-Langenheine et al. [Phys. Rev. Lett. 95, 156402 (2005)]. increase linewidth with decreasing shows local-field redistribution, consistent formation charge-density waves stripes. For comparison, we studied, particular, grandmother all planar antiferromagnets K2NiF4 paramagnetic state using natural abundant hyperfine fields both two-dimensional compounds appear be remarkably small, well explained super (transferred) interaction. In K2NiF4, dependence susceptibility Knight cannot brought onto simple scaling curve. This unique feature ascribed different sensitivity correlations these two parameters.