Electronic structure and magnetism in transition metals doped 8-hydroxy-ouinoline aluminum

Abstract

We report the room-temperature ferromagnetism in transition metals (Co, Ni)-doped 8-hydroxy-quinoline aluminum (Alq(3)) by thermal coevaporation of high purity metal and Alq(3) powders. For 5% Co-doped Alq(3), a maximum magnetization of similar to 0.33 mu(B)/Co at 10 K was obtained and ferromagnetic behavior was observed up to 300 K. The Co atoms interact chemically with 0 atoms and provide electrons to Alq(3), forming new states acting as electron trap sites. From this, it is suggested that ferromagnetism may be associated with the strong chemical interaction of Co atoms and Alq(3) molecules.