Synthesis and physical properties of CeRu$_2$As$_2$ and CeIr$_2$As$_2$

Kangqiao Cheng; Xiaobo He; Haiyang Yang; Binjie Zhou; Yuke Li; Yongkang Luo

doi:10.1103/PhysRevB.100.205121

paper

Synthesis and physical properties of CeRu $_{2}$ As $_{2}$ and CeIr $_{2}$ As $_{2}$

arXiv:1909.04447 · doi:10.1103/PhysRevB.100.205121

Abstract

We studied the physical properties of two Kondo-lattice compounds, CeRu $_{2}$ As $_{2}$ and CeIr $_{2}$ As $_{2}$ , by a combination of electric transport, magnetic and thermodynamic measurements. They are of ThCr $_{2}$ Si $_{2}$ -type and CaBe $_{2}$ Ge $_{2}$ -type crystalline structures, respectively. CeRu $_{2}$ As $_{2}$ shows localized long-range antiferromagnetic ordering below $T_{N}$ =4.3 K, with a moderate electronic Sommerfeld coefficient $γ_{0}$ =35 mJ/mol $\cdot$ K $^{2}$ . A field-induced metamagnetic transition is observed near 2 T below $T_{N}$ . Magnetic susceptibility measurements on aligned CeRu $_{2}$ As $_{2}$ powders suggest that it has an easy axis and that the cerium moments align uniaxially along $c$ axis. In contrast, CeIr $_{2}$ As $_{2}$ is a magnetically nonordered heavy-fermion metal with enhanced $γ_{0}$ $>$ 300 mJ/mol $\cdot$ K $^{2}$ . The initial onset Kondo temperatures of the two compounds are respectively 6 K and 30 K. We discuss the role of the crystal structure to the strength of Kondo coupling. This work provides two new dense Kondo-lattice materials for further investigations on electronic correlation, quantum criticality and heavy-electron effects.

8 pages, 5+2 figures, 1 table

Synthesis and physical properties of CeRu2​As2​ and CeIr2​As2​

Abstract

Synthesis and physical properties of CeRu $_{2}$ As $_{2}$ and CeIr $_{2}$ As $_{2}$