Growth, magnetic and transport properties of Li‐doped SrFe2As2 single crystals

Abstract

Single crystals of Li‐doped SrFe2As2 up to 2 × 2 mm2 in size were grown from LiCl flux. The obtained material contains only a minor amount of Li, but shows distinct differences in physical properties as compared to the pure material synthesized via other techniques. It orders antiferromagnetically below 6.2 K and does not show any indication of superconductivity above 1.2 K. The large negative Curie–Weiss temperature θW⊥ = −206.5 (μW|| = −200.5 K) points to the dominance of antiferromagnetic Fe–Fe interactions. The reduced effective magnetic moments of Fe2+ μeff⊥ = 2.31 μB (μeff|| = 2.27 μB) indicate itinerant character of magnetism in this system. According to electrical resistivity measurements this material is a semimetal. In the temperature range of 12–70 K ρ(T) follows a Fermi‐liquid T2‐dependence. In the vicinity of antiferromagnetic ordering ρ(T) deviates from Fermi‐liquid behavior. Below about 12 K, a transport law of the obtained single crystals requires a substantial linear non‐Fermi contribution to successfully describe the data.