Magnetic properties of heavy fermion compound Ce₅Si₄ with chiral structure

The low-temperature magnetic properties of Ce₅Si₄ with a chiral structure have been studied by electrical resistivity, heat capacity, and magnetization measurements using single-crystalline samples. It is found that Ce₅Si₄ is an antiferromagnet with moderately correlated electronic states. The resistivity decreases strongly under magnetic fields, indicating scaling behavior based on the Coqblin–Schrieffer model. The obtained characteristic energy scale of the Kondo effect is clearly anisotropic for the magnetic field H ∥ a-axis and H ∥ c-axis in the tetragonal structure, possibly related to the anisotropic antiferromagnetic phase. Furthermore, in the antiferromagnetic phase, a shoulderlike crossover anomaly is observed in C=T. A possible scenario is that non-ordered Ce atoms exist even below T_N in this chiral system.