Room-Temperature Ferromagnetism in InSb-Mn Nanowires

The successful synthesis of one-dimensional nanostructures of a narrow band gap semiconductor, exhibiting a ferromagnetic response at room temperature, is reported. High-quality nanowires of InSb-Mn have been produced by template-assisted pulse electrodeposition. Detailed structural and spectroscopic characterizations revealed good crystallinity, a narrow size distribution of the nanostructures, and the ability to control the Mn doping level. The dominating magnetic response at a cryogenic temperature evolves with an increasing Mn concentration from paramagnetic through antiferromagnetic to ferromagnetic. A robust ferromagnetic response of InSb nanowires doped with 2.5% at. of Mn is retained up to a Curie temperature of nearly 500 K.