CeAu2In4: A candidate of quasi-one-dimensional antiferromagnetic Kondo lattice*

Needle-like single crystals of CeAu2In4 have been grown from In flux and characterized as a new candidate of quasi-one-dimensional Kondo lattice compound by crystallographic, magnetic, transport, and specific-heat measurements down to very low temperatures. We observe an antiferromagnetic transition at T (N) approximate to 0.9 K, a highly non-mean-field profile of the corresponding peak in specific heat, and a large Sommerfeld coefficient gamma = 369 mJ.mol(-1).K-2. The Kondo temperature T (K) is estimated to be 1.1 K, being low and comparable to T (N). While Fermi liquid behavior is observed deep into the magnetically ordered phase, the Kadowaki-Woods ratio is much reduced relative to the expected value for Ce compounds with Kramers doublet ground state. Markedly, this feature shares striking similarities to that of the prototypical quasi-one-dimensional compounds YbNi4P2 and CeRh6Ge4 with tunable ferromagnetic quantum critical point. Given the shortest Ce-Ce distance along the needle direction, CeAu2In4 appears to be an interesting model system for exploring antiferromagnetic quantum critical behaviors in a quasi-one-dimensional Kondo lattice with enhanced quantum fluctuations.

Automated summary

Needle-like single crystals of CeAu2In4 have been grown and characterized as a new candidate of quasi-one-dimensional Kondo lattice compound, showing antiferromagnetic transition, Fermi liquid behavior, and a low Kondo temperature. The system exhibits similarities to YbNi4P2 and CeRh6Ge4 with a tunable ferromagnetic quantum critical point. CeAu2In4 appears to be an interesting model system for exploring antiferromagnetic quantum critical behaviors in a quasi-one-dimensional Kondo lattice with enhanced quantum fluctuations.