Crystal Electric Field (CEF) Effect in CeIr3Ge7 and YbIr3Ge7

We recently discovered new members of the stoichiometric 1-3-7 family of crystals including YbRh3Si7, YbIr3Ge7, CeIr3Ge7, and YbIr3Si7, whose magnetic and transport properties reflect large crystal electric field(CEF) anisotropy. Inelastic neutron scattering measurements on CeIr3Ge7 and YbIr3Ge7 will allow us to directly measure their CEF transitions from which we can then parameterize their single ion Hamiltonians. This analysis will definitively establish the nature of their spin anisotropies and the g-tensor of their ground state doublet, from which we can determine the size of the magnetic moment reduced by crystal field effects. Our studies thus far have revealed the importance of single ion properties in these two materials and it is thus crucial that we directly measure their CEF schemes to understand the origins of these effects.

我们近期发现了化学计量比1-3-7型晶体家族的新成员，包括YbRh₃Si₇、YbIr₃Ge₇、CeIr₃Ge₇以及YbIr₃Si₇。这类晶体的磁学与输运性质展现出显著的晶体电场（crystal electric field, CEF）各向异性。针对CeIr₃Ge₇与YbIr₃Ge₇开展的非弹性中子散射（inelastic neutron scattering）测量，可直接获取其晶体电场跃迁信息，进而对其单离子哈密顿量（single ion Hamiltonians）进行参数化。该分析将明确厘清其自旋各向异性（spin anisotropies）与基态二重态（ground state doublet）的g张量（g-tensor）的本质，借此可求得受晶体电场效应削弱的磁矩幅值。截至目前的研究已揭示出单离子性质在这两种材料中的重要性，因此直接测得其晶体电场能级结构以阐明此类效应的起源，便显得尤为关键。