磁性單電子電晶體中自旋堆積所引發的磁電容之探測

Probing Spin Accumulation induced Magnetocapacitance in a Single Electron Transistor

呂德輝(Teik-Hui Lee)

指導教授 ： 陳啟東

共同指導教授 ： 張嘉升(Chia-Seng Chang)

國立臺灣大學/理學院/物理研究所/博士(2015年)

https://doi.org/10.6342/NTU.2015.00250

摘要

無資料

關鍵字

磁電容 ； 自旋堆積 ； 磁性單電子電晶體

並列摘要

We show that non-equilibrium spin accumulation can induce tunnel magnetocapacitance through the formation of a tiny charge dipole. This dipole can effectively give rise to an additional serial capacitance, which represents an extra charging energy that the tunneling electrons would encounter. In the sequential tunneling regime, this extra energy can be understood as the energy required for a single spin to flip. A ferromagnetic single-electron-transistor with tunable magnetic configuration is utilized to demonstrate the proposed mechanism. It is found that the extra threshold energy is experienced only by electrons entering the islands, bringing about asymmetry in the measured Coulomb diamond. This asymmetry is an unambiguous evidence of spin accumulation induced tunnel magnetocapacitance, and the measured magnetocapacitance value is as high as 40%.

並列關鍵字

magnetocapacitance ； spin accumulation ； spin flip ； spin diffusion length ； single electron transistor ； Coulomb diamond

參考文獻

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