Marcano N, Espeso J I, Gómez Sal J C
J Phys Condens Matter. 2013 Dec 4;25(48):484004. doi: 10.1088/0953-8984/25/48/484004.
We report the revisited magnetic phase diagram for the Kondo (ferromagnetic and antiferromagnetic) CeNi1−xCux series based on ac–dc magnetization, heat capacity, neutron diffraction and muon spectroscopy down to very low temperatures (~100 mK). An evolution from antiferromagnetism, observed for Cu-rich alloys (0.8 ≤ x ≤ 1), to clustered-ferromagnetism, seen for samples with 0.3 ≤ x ≤ 0.6, and then to spin-glass for 0.1 ≤ x ≤ 0.2, has been observed. The clustered-ferromagnetic phase emerges from a cluster-glass state without any indication of Curie temperature. For the samples adjacent to the magnetic–nonmagnetic crossover 0.1 ≤ x ≤ 0.2, only the cluster-glass state is observed due to the weakening of the RKKY interactions. We discuss the emerging phenomena taking into account the cluster-percolative scenario proposed for this series and the role of the interactions involved along the whole series. The proximity to a T = 0 K spin-glass quantum phase transition in the phase diagram is discussed.
我们报道了基于交流-直流磁化强度、热容量、中子衍射和μ子光谱，直至极低温度（约100 mK）的近藤（铁磁和反铁磁）CeNi1−xCux系列的重新审视的磁相图。已观察到从富铜合金（0.8 ≤ x ≤ 1）中观察到的反铁磁性，到0.3 ≤ x ≤ 0.6的样品中出现的簇状铁磁性，再到0.1 ≤ x ≤ 0.2的自旋玻璃态的演变。簇状铁磁相从簇玻璃态出现，没有任何居里温度的迹象。对于接近磁-非磁交叉点0.1 ≤ x ≤ 0.2的样品，由于RKKY相互作用减弱，仅观察到簇玻璃态。我们考虑为此系列提出的簇渗流情景以及整个系列中所涉及相互作用的作用，讨论了出现的现象。讨论了相图中接近T = 0 K自旋玻璃量子相变的情况。
