Detecting excitation and magnetization of individual dopants in a semiconductor
Detecting excitation and magnetization of individual dopants in a semiconductor
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DOI：
10.1038/nature09519
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发表时间：
2010-10-28
期刊：
影响因子：
64.8
通讯作者：
Wiesendanger, Roland
中科院分区：
文献类型：
--
作者：
Khajetoorians, Alexander A.;Chilian, Bruno;Wiesendanger, Roland
掺杂到半导体中的单个磁性原子是自下而上自旋电子器件和量子逻辑门（1-3）的有前途的构建块。此外，它为原子尺度研究稀磁半导体中的基本效应（如磁性）提供了一个完美的模型系统（4）。然而，到目前为止，半导体中的掺杂剂还没有通过具有原子分辨率的磁敏感技术来研究，该磁敏感技术将原子结构与掺杂剂的磁性相关联。在这里，我们显示了电激发和读出的自旋与一个单一的磁性掺杂剂在半导体主机。我们使用自旋分辨扫描隧道光谱测量自旋激发和磁化曲线的单个铁表面掺杂剂嵌入在二维电子气局限于锑化铟（110）表面。掺杂剂的作用类似于孤立的量子自旋，其状态由实质上的磁各向异性控制，该磁各向异性迫使自旋位于表面平面中。这一结果得到了我们的第一原理计算的证实。所展示的方法为自旋电子学领域更广泛研究的样品系统的研究开辟了新的途径，即GaAs中的Mn（参考文献5），半导体量子点中的磁性离子（3），金刚石中的氮空位中心（6）和硅中的磷自旋（7）。
An individual magnetic atom doped into a semiconductor is a promising building block for bottom-up spintronic devices and quantum-logic gates(1-3). Moreover, it provides a perfect model system for the atomic-scale investigation of fundamental effects such as magnetism in dilute magnetic semiconductors(4). However, dopants in semiconductors so far have not been studied by magnetically sensitive techniques with atomic resolution that correlate the atomic structure with the dopant's magnetism. Here we show electrical excitation and read-out of a spin associated with a single magnetic dopant in a semiconductor host. We use spin-resolved scanning tunnelling spectroscopy to measure the spin excitations and the magnetization curve of individual iron surface-dopants embedded within a two-dimensional electron gas confined to an indium antimonide (110) surface. The dopants act like isolated quantum spins the states of which are governed by a substantial magnetic anisotropy that forces the spin to lie in the surface plane. This result is corroborated by our first principles calculations. The demonstrated methodology opens new routes for the investigation of sample systems that are more widely studied in the field of spintronics-that is, Mn in GaAs (ref. 5), magnetic ions in semiconductor quantum dots(3), nitrogen-vacancy centres in diamond(6) and phosphorus spins in silicon(7).