Magnetization Reversal Mechanism for CoFeB Ferromagnetic Nanotube Arrays
LIU Hai-Rui1,2, S. Shamaila2, CHEN Jun-Yang2, R. Sharif2, LU Qing-Feng1, HAN Xiu-Feng2
1College of Physics and Information Engineering, Henan Normal University, Xinxiang 4530072State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190
Magnetization Reversal Mechanism for CoFeB Ferromagnetic Nanotube Arrays
LIU Hai-Rui1,2, S. Shamaila2, CHEN Jun-Yang2, R. Sharif2, LU Qing-Feng1, HAN Xiu-Feng2
1College of Physics and Information Engineering, Henan Normal University, Xinxiang 4530072State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190
摘要CoFeB nanotube arrays are fabricated in anodic aluminum oxide (AAO) membranes and track etched polycarbonate (PCTE) membranes by using an electrochemical method, and their magnetic properties are investigated by vibrating sample magnetometry. The coercivity Hc and remanent squareness SQ of these CoFeB nanotube arrays are derived from hysteresis loops as a function of angle between the field and tube axis. The Hc(θ) curves for CoFeB nanotube arrays in AAO and PCTE membranes show M-type variation, while they change shape from M to mountain-type as the tube length increases. However, the overall easy axis perpendicular to tube axis does not change with tube length. The different angular dependences are attributed to different magnetization reversal mechanisms.
Abstract：CoFeB nanotube arrays are fabricated in anodic aluminum oxide (AAO) membranes and track etched polycarbonate (PCTE) membranes by using an electrochemical method, and their magnetic properties are investigated by vibrating sample magnetometry. The coercivity Hc and remanent squareness SQ of these CoFeB nanotube arrays are derived from hysteresis loops as a function of angle between the field and tube axis. The Hc(θ) curves for CoFeB nanotube arrays in AAO and PCTE membranes show M-type variation, while they change shape from M to mountain-type as the tube length increases. However, the overall easy axis perpendicular to tube axis does not change with tube length. The different angular dependences are attributed to different magnetization reversal mechanisms.
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2009, Vol. 26 
