Imaging and magnetometry of switching in nanometer‐scale iron particles
Imaging and magnetometry of switching in nanometer‐scale iron particles
复制标题
纳米级铁颗粒切换的成像和磁力测量
DOI：
10.1063/1.118032
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
S. V. Molnár
中科院分区：
文献类型：
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作者：
S. Gider;Jing Shi;D. Awschalom;P. Hopkins;K. Campman;A. Gossard;A. Kent;S. V. Molnár
通过低温霍尔磁强计和室温磁力显微镜研究了纳米尺度（直径<40 nm）铁颗粒阵列中的反转机制。低温（20 K）下净阵列磁化的旋转以可逆和不可逆模式发生，后者由巴克豪森跳跃揭示。在室温下的空间分辨测量表明，颗粒是单域的剩磁和矫顽力，表明它们不是超顺磁性的。观察到单个颗粒在平行于颗粒生长方向的优选磁方向之间的小场范围（<10 Oe）内不可逆地切换。阵列的缩放提供了45 Gbit/in.2水平的磁存储的可能性，比当前技术高出近50倍。
The reversal mechanisms in arrays of nanometer‐scale (<40 nm diameter) iron particles are studied by low‐temperature Hall magnetometry and room‐temperature magnetic force microscopy. Rotation of the net array magnetization at low temperatures (20 K) occurs by both reversible and irreversible modes, the latter revealed by Barkhausen jumps. Spatially resolved measurements at room temperature show the particles to be single domain with remanence and coercivity indicating they are not superparamagnetic. Individual particles are observed to switch irreversibly over a small field range (<10 Oe) between preferred magnetic directions parallel to the growth direction of the particles. Scaling of the arrays offers the possibility of magnetic storage at the 45 Gbit/in.2 level, nearly 50 times greater than current technology.