Freitas G S, Piva M M, Grossi R, Jesus C B R, Souza J C, Christovam D S, Oliveira N F, Leão J B, Adriano C, Lynn J W, Pagliuso P G
Instituto de Física "Gleb Wataghin", UNICAMP, Campinas-SP, 13083-859, Brazil.
Programa de Pós-Graduação em Física, Campus Prof. José Aluísio de Campos, UFS, 49100-000, São Cristóvão, SE, Brazil.
Phys Rev B. 2020 Sep;102(11). doi: 10.1103/PhysRevB.102.115129.
We have performed X-ray powder diffraction, magnetization, electrical resistivity, heat capacity and inelastic neutron scattering (INS) to investigate the physical properties of the intermetallic series of compounds . These compounds crystallize in a tetragonal structure with space group and present antiferromagnetic transition temperatures ranging from 3.6 K to 16 K. Remarkably, the magnetization easy axis changed along the series, which is closely related to the variations of the tetragonal crystalline electric field (CEF) parameters. This evolution was analyzed using a mean field model, which included an anisotropic nearest-neighbor interactions and the tetragonal CEF Hamiltonian. We obtained the CEF parameters by fitting the magnetic susceptibility data with the constraints given by the INS measurements. More broadly, we discuss how this CEF evolution can affect the Kondo physics and the search for a superconducting state in this family.
我们进行了X射线粉末衍射、磁化强度、电阻率、热容量和非弹性中子散射（INS）实验，以研究该金属间化合物系列的物理性质。这些化合物结晶为具有空间群的四方结构，呈现出3.6 K至16 K的反铁磁转变温度。值得注意的是，沿该系列磁化易轴发生了变化，这与四方晶体电场（CEF）参数的变化密切相关。使用平均场模型分析了这种演化，该模型包括各向异性最近邻相互作用和四方CEF哈密顿量。我们通过将磁化率数据与INS测量给出的约束条件进行拟合来获得CEF参数。更广泛地说，我们讨论了这种CEF演化如何影响该家族中的近藤物理和超导态的探索。
