Metamagnetic Crossover In The Quasikagome Ising Kondo-Lattice Compound Ceirsn

The Ce atoms in CeIrSn form a quasikagome lattice in the hexagonal c plane. Our single-crystal x-ray diffraction analysis has confirmed the absence of superstructure in the ZrNiAl-type structure. Motivated by the recent observation of quantum critical behaviors in the isostructural and isoelectronic compound CeRhSn, we have studied low-temperature properties of single-crystalline samples of CeIrSn by measuring the electrical resistivity, magnetic susceptibility chi, magnetization M, and specific heat C down to 0.05 K. Our study does not show evidence of a long-range magnetic ordering down to the lowest temperature. The chi(T ) data show an Ising character, chi(c) >> chi(a) , and power-law behaviors at low temperatures: chi(c) proportional to T-0.8 and chi(a) proportional to T-0.6. When external field B is applied along the a axis, both M(B) and C(B)/T exhibit metamagnetic anomalies at 5.5 T, which resemble those observed in CeRhSn at 3.5 T. We attribute the metamagnetic crossover under in-plane magnetic fields to the alleviation of magnetic frustration inherent in the quasikagome Ising Kondo lattice.