Title :
Zeeman Splitting-Induced Positive Magnetoresistance in Co-Doped ZnO and Co-Doped Cu
O Ferromagnetic Nanoparticles
Author :
Tian, Yufeng ; Antony, Jiji ; Souza, Ryan ; Yan, Shishen ; Qiang, You
Abstract :
Magnetoresistance of cobalt-doped zinc oxide and cuprous oxide ferromagnetic nanoparticles with different cobalt concentrations are studied. Zeeman splitting effect is found to play a key role in the electrical transport of our cobalt-doped oxide ferromagnetic nanoparticles. We emphasize that the existence of large Zeeman splitting effect can be used in spintronics devices, because a very large and linear positive magnetoresistance (PMR) up to 780% is observed in the low field for the Co-doped ZnO. Small PMR in Co-doped Cu2O relates to its small p-d exchange interaction. Codoping with other transition metals in Cu2O is suggested to improve the ferromagnetism and magnetoresistance.
Keywords :
II-VI semiconductors; Zeeman effect; cobalt; copper compounds; exchange interactions (electron); ferromagnetic materials; magnetic particles; magnetoresistance; nanoparticles; semiconductor doping; semiconductor materials; semimagnetic semiconductors; wide band gap semiconductors; zinc compounds; Cu2O:Co; Zeeman splitting-induced positive magnetoresistance; ZnO:Co; cobalt-doped cuprous oxide; cobalt-doped zinc oxide; doping; electrical transport; exchange interaction; ferromagnetic nanoparticles; spintronics devices; Cu$_{2}$O; ZnO; nanoparticle; positive magnetoresistance;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2008.2002364