Spin polarization and magneto-Coulomb oscillations in ferromagnetic single electron devices
Spin polarization and magneto-Coulomb oscillations in ferromagnetic single electron devices
复制标题
铁磁单电子器件中的自旋极化和磁库仑振荡
DOI：
10.1143/jpsj.67.2852
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发表时间：
1998
影响因子：
1.7
通讯作者：
Y. Ootuka
中科院分区：
文献类型：
--
作者：
K. Ono;H. Shimada;Y. Ootuka
在各种铁磁单电子器件中检查了在铁磁单电子晶体管中观察到的由于外部磁场引起的单电子重新填充而产生的磁库仑振荡。对于由 Ni 和 Co 电极制成的双结和三结器件，无论电极的配置如何，随着磁场的增加，单电子重新填充总是从 Ni 电极到 Co 电极发生。磁库仑振荡的周期与单电子充电能量成正比。所有这些特征都可以通过塞曼效应引起具有非零自旋极化的铁磁金属的费米能量变化的机制来一致地解释。实验确定的 Ni 和 Co 的自旋极化均为负，并且 Ni 的幅度大于 Co，正如计算的能带结构所预期的那样。
The magneto-Coulomb oscillation due to the single electron repopulation induced by external magnetic field, observed in a ferromagnetic single electron transistor is examined in various ferromagnetic single electron devices. In case of double- and triple-junction devices made of Ni and Co electrodes, the single electron repopulation always occurs from Ni to Co electrodes with increasing magnetic field, irrespective of the configurations of the electrodes. The period of the magneto-Coulomb oscillation is proportional to the single electron charging energy. All these features are consistently explained by the mechanism that the Zeeman effect induces changes of the Fermi energy of the ferromagnetic metal having a non-zero spin polarizations. Experimentally determined spin polarizations are negative for both Ni and Co and the magnitude is larger for Ni than Co as expected from the calculated band structures.