中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 15 No. 2 April 2005 |
QIU Hong-mei(邱紅梅)1, WANG Feng-ping(王風平)1,
WU Ping(
（1. Department of Physics, University of Science and Technology Beijing,
Beijing 100083, China;
2. Department of Materials Physics and Chemistry,
University of Science and Technology Beijing, Beijing 100083, China;
3. Department of Physics and Astronomy, University of Delaware,
Newark 19716, USA）
Abstract: The CuO doped with 5%-20% Mn(molar fraction) solids were sintered from CuO and MnO2 powder at high temperature(1273K) for 8h. X-ray diffraction was used to determine the solid crystallinity and to address the formation of secondary phases. It is found that it is difficult to achieve pure Cu1-xMnxO phase using standard solid phase reaction. However, sintering under a pressure of 27.7MPa significantly reduces the undesirable second phase CuMn2O4, providing a route to achieve pure Cu1-xMnxO phase. SQUID magnetometry was employed to characterize the magnetic properties. Mn-doped CuO presents ferromagnetic characteristics below 70K. Electrical transport properties were measured in a current-perpendicular-to-plane(CPP) geometry using the PPMS, which suggests variable-range hopping mechanism.
Key words: Mn-doped CuO; diluted magnetic semiconductor; solid crystallinity; hopping mechanism
