Silicene-based spin-filter device: impact of random vacancies
Silicene-based spin-filter device: impact of random vacancies
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DOI：
10.1088/2053-1583/3/2/025006
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发表时间：
2016-03
期刊：
影响因子：
5.5
通讯作者：
C. Núñez;F. Domínguez-Adame;P. Orellana;L. Rosales;Rudolf A. Römer
中科院分区：
文献类型：
--
作者：
C. Núñez;F. Domínguez-Adame;P. Orellana;L. Rosales;Rudolf A. Römer
我们提出了一种基于硅烯纳米粒子的混合自旋过滤器器件。生长在纳米颗粒顶部的铁电聚合物分裂自旋向上和自旋向下的电子带，并产生电导的自旋极化。特别是，我们研究了这种自旋过滤器设备的性能上的空位的随机分布的影响。无序诱导电子的安德森局域化，我们发现，局域化长度强烈依赖于电子自旋。通过调整源极接触的费米能级，只有具有一个自旋取向的电子可以到达漏极接触，因为它们的局部化长度大于器件的长度。自旋相反的电子在很大程度上被反向反射。然后电导变成自旋极化，器件表现为准半金属。我们的结论是，一个中等浓度的空位对设备的自旋过滤器的能力影响不大，打开的可能性，使用它作为一个可调的极化电子源。
We propose a hybrid spin-filter device based on a silicene nanoribbon. A ferroelectric polymer grown on top of the nanoribbon splits spin-up and spin-down electron bands and gives rise to a spin polarisation of the conductance. In particular, we study the effects of a random distribution of vacancies on the performance of this spin-filter device. Disorder induces Anderson localisation of electrons and we find that the localisation length strongly depends on the electron spin. By adjusting the Fermi level of the source contact, only electrons with one spin orientation can reach the drain contact because their localisation length is larger than the length of the device. Electrons with opposite spin are largely back-reflected. Electric conductance then becomes spin polarised and the device behaves as a quasi-half-metal. We conclude that a moderate concentration of vacancies has little impact on the spin-filter capabilities of the device, opening the possibility to using it as a tuneable source of polarised electrons.