Spin-glass-like behavior in ZnCrAlSe

Overview & Synopsis

The magnetic and electrical properties of the Al-doped polycrystalline spinels ZnCrAlSe (0.13 ≤ ≤ 0.55) with the antiferromagnetic order and semiconducting behavior were investigated. A complex antiferromagnetic structure below a Néel temperature ≈ 23K for the samples with up to 0.4 contrasting with the strong ferromagnetic interactions evidenced by a large positive Curie-Weiss temperature decreasing from 62.2K for =0.13 to 37.5K for =0.55 was observed. Detailed investigations revealed a divergence between the zero-field-cooling (ZFC) and field-cooling (FC) susceptibilities at temperature smaller than suggesting bond frustration due to competing ferromagnetic and antiferromagnetic exchange interactions in the compositional range 0.13 ≤ z ≤ 0.4. Meanwhile, for =0.55 a spin-glass-like behavior of cluster type with randomly oriented magnetic moments is observed as the ZFC-FC splitting goes up to the freezing temperature =11.5K and the critical fields connected both with a transformation of the antiferromagnetic spin spiral via conical magnetic structure into ferromagnetic phase disappear.