Antiferromagnetic Ordering and Transport Anomalies in Single-Crystalline CeAgAs₂

Abstract

Single crystals of the ternary cerium arsenide CeAgAs2 were grown by chemical vapor transport. They were studied by means of x-ray diffraction, magnetization, heat capacity and electrical transport measurements. The experimental research was supplemented with electronic band structure calculations. The compound was confirmed to order antiferromagnetically at the Néel temperature of 4.9 K and to undergo metamagnetic transition in a field of 0.5 T at 1.72 K. The electrical resistivity shows distinct increase at low temperatures, which origin is discussed in terms of pseudo-gap formation in the density of states at the Fermi level and quantum corrections to the resistivity in the presence of atom disorder due to crystal structure imperfections.

Keywords

• cerium pnictides
• antiferromagnetism
• metamagnetism
• Kondo effect
• pseudo-gap