Tunneling spectroscopy and magnon excitation in Co2FeAl/MgO/Co-Fe magnetic tunnel junctions
Tunneling spectroscopy and magnon excitation in Co2FeAl/MgO/Co-Fe magnetic tunnel junctions
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Co2FeAl/MgO/Co-Fe 磁性隧道结中的隧道光谱和磁振子激发
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
Andy Thomas
中科院分区：
文献类型：
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作者：
D. Ebke;V. Drewello;M. Schäfers;G. Reiss;Andy Thomas
制备了以Heusler化合物Co_2FeAl为软电极的磁性隧道结。钉扎Co-Fe用作硬参比电极。在13 K时，该结的隧道磁电阻率高达273%.用隧道谱研究了其电子输运特性，讨论了dI/dV和d2 I/dV 2。在平行磁状态下，隧穿谱相对于偏置电压是不对称的，具有明显的偏置无关区域。在反平行状态下，对偏置电压的依赖性强得多，曲线是对称的。这一发现可以用Co2 FeAl的少数态密度的间隙来解释。
Magnetic tunnel junctions with the Heusler compound Co2FeAl as the soft electrode are prepared. Pinned Co–Fe is used as the hard reference electrode. The junctions show a high tunnel magnetoresistance ratio of 273% at 13 K. The electronic transport characteristics are investigated by tunneling spectroscopy—dI/dV and d2I/dV2 are discussed. In the parallel magnetic state the tunneling spectra are asymmetric with respect to the bias voltage, with a pronounced bias-independent region. In the antiparallel state the dependence on bias voltage is much stronger and the curves are symmetric. The findings can be explained with a gap in the minority density of states of Co2FeAl.