Liu Mingfeng, Jin Tianli, Hao Liang, Cao Jiangwei, Wang Ying, Wu Dongping, Bai Jianmin, Wei Fulin
Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou, 730000 People's Republic of China.
Nanoscale Res Lett. 2015 Apr 2;10:161. doi: 10.1186/s11671-015-0863-x. eCollection 2015.
The effects of Ru and Ag cap layers on the microstructure and magnetic properties of the FePt ultrathin films have been investigated. The results indicate that i) The Ag cap layer segregates from the FePt/Ag bilayer, lowers the FePt ordering temperature, promotes the FePt thin films to form island structure, and enhances the coercivity; ii) The Ru cap layer increases the FePt ordering temperature, helps to maintain smooth continuous structure film, and restrains the FePt (001) orientation and perpendicular magnetic anisotropy (PMA). The effects become more pronounced for the 3-nm-thick FePt thin films. The effects can be mainly attributed to the different melting point and thermal expansion stress between the cap layer and FePt thin films.
研究了钌（Ru）和银（Ag）帽层对FePt超薄膜微观结构和磁性能的影响。结果表明：i）Ag帽层从FePt/Ag双层中分离出来，降低了FePt的有序温度，促进FePt薄膜形成岛状结构，并提高了矫顽力；ii）Ru帽层提高了FePt的有序温度，有助于保持光滑连续的结构薄膜，并抑制FePt（001）取向和垂直磁各向异性（PMA）。对于3nm厚的FePt薄膜，这些影响更为明显。这些影响主要归因于帽层与FePt薄膜之间不同的熔点和热膨胀应力。
