Journal of the Korean Physical Society

pISSN 0374-4884 eISSN 1976-8524


J. Korean Phy. Soc. 2007; 50(6): 1711-1715

Published online June 15, 2007

Copyright © The Korean Physical Society.

Spatially-Resolved Study of Magnetic Properties of Mn-Doped ZnO Quantum Wires

G. N. Panin, A. N. Baranov, T. W. Kang, S. K. Min and H. J. Kim


ZnO nanowires prepared by thermal growth following direct chemical synthesis and doped by Mn and by Mn and Sn impurities were investigated. The nanowires show a single crystal structure and a strong blue shift of the near band edge luminescence, which is attributed to the quantum confinement effect. The magnetic susceptibility of the quantum wires as a function of temperature demonstrated a Curie-Weiss behavior. Hysteresis with a coercive field $<$200 Oe was clearly observed in the magnetization versus field curves at 300 K. Increasing the Mn concentration by Mn and Sn co-doping significantly increased the magnetic hysteresis and the ferromagnetic behavior of the nanowires. Magnetic force microscopy measurements with high spatial resolution revealed a magnetic domain structure in the individual wires. The magnetic domains align perpendicular to the surface and can be controlled by using an external magnetic field.

Keywords: ZnO, Quantum wires, Ferromagnetism, Magnetic force microscopy