Magnetoresistance through a ferromagnet/superconductor/ferromagnet junction on the surface of a topological insulator
Magnetoresistance through a ferromagnet/superconductor/ferromagnet junction on the surface of a topological insulator
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DOI：
10.7567/apex.7.023001
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发表时间：
2014-01
影响因子：
2.3
通讯作者：
Yanling Yang;K. Wei;C. Bai
中科院分区：
文献类型：
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作者：
Yanling Yang;K. Wei;C. Bai
我们表明，无论哪种安德烈夫反射（逆反射或镜面反射）占主导地位，都可以在拓扑绝缘体表面上产生铁磁体/超导体/铁磁体结的正磁阻和负磁阻。相反，在基于石墨烯的结中，在逆安德烈夫反射的情况下无法观察到负磁阻。对于长结，与逆安德烈夫反射相反，镜面安德烈夫反射会产生正的过剩磁阻。我们进一步预测磁阻振荡作为偏置电压的函数，并且只有平行于结界面的磁化分量对磁阻有影响。
We show that one may create both positive and negative magnetoresistance of a ferromagnet/superconductor/ferromagnet junction on the surface of a topological insulator no matter which Andreev reflection (retro- or specular-) is dominant. In contrast, in a graphene-based junction, the negative magnetoresistance cannot be observed in the case of retro-Andreev reflection. For a long junction, in contrast to retro-Andreev reflection, specular-Andreev reflection gives rise to a positive excess magnetoresistance. We further predict the oscillation of magnetoresistance as a function of bias voltage, and only the magnetization component parallel to the junction interface has an influence on the magnetoresistance.