Tunable finite-sized chains to control magnetic relaxation
Tunable finite-sized chains to control magnetic relaxation
复制标题
可调节的有限尺寸链来控制磁弛豫
DOI：
10.1103/physrevb.95.014406
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发表时间：
2016
影响因子：
3.7
通讯作者：
T. Gredig
中科院分区：
文献类型：
--
作者：
P. D. Ekstrand;Daniel J. Javier;T. Gredig
利用酞菁铁薄膜研究了低维铁离子链的磁性动力学。沉积温度通过将平均晶体尺寸限制在40至110 nm的范围内来改变薄膜生长期间的扩散长度。使用一种常见的单链磁体的方法，每个链长度的磁弛豫时间从时间剩磁数据确定，并适合在低于5 K的温度范围内的拉伸指数形式，磁滞的发病。一个与温度无关的主曲线是通过缩放剩磁由其弛豫时间，以适应自旋反转的能量势垒，和单自旋弛豫时间。发现95 K的能垒与链长无关。相比之下，单自旋弛豫时间随着较长的链从1 ps以下增加到800 ps。我们发现，薄膜提供了纳米结构来控制磁弛豫和一个测试平台，以研究在低维磁性系统中的有限尺寸效应。
The magnetic dynamics of low-dimensional iron ion chains have been studied with regards to the tunable finite-sized chain length using iron phthalocyanine thin films. The deposition temperature varies the diffusion length during thin film growth by limiting the average crystal size in the range from 40 to 110 nm. Using a method common for single chain magnets, the magnetic relaxation time for each chain length is determined from temporal remanence data and fit to a stretched exponential form in the temperature range below 5 K, the onset for magnetic hysteresis. A temperature-independent master curve is generated by scaling the remanence by its relaxation time to fit the energy barrier for spin reversal, and the single spin relaxation time. The energy barrier of 95 K is found to be independent of the chain length. In contrast, the single spin relaxation time increases with longer chains from under 1 ps to 800 ps. We show that thin films provide the nano-architecture to control magnetic relaxation and a testbed to study finite-size effects in low-dimensional magnetic systems.