Department of Physics, University of California, 1 Shields Ave, Davis, CA, 95616, USA.
Materials Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA, 94720, USA.
Nat Commun. 2018 Aug 17;9(1):3306. doi: 10.1038/s41467-018-05823-z.
The dilute magnetic semiconductors have promise in spin-based electronics applications due to their potential for ferromagnetic order at room temperature, and various unique switching and spin-dependent conductivity properties. However, the precise mechanism by which the transition-metal doping produces ferromagnetism has been controversial. Here we have studied a dilute magnetic semiconductor (5% manganese-doped gallium arsenide) with Bragg-reflection standing-wave hard X-ray angle-resolved photoemission spectroscopy, and resolved its electronic structure into element- and momentum- resolved components. The measured valence band intensities have been projected into element-resolved components using analogous energy scans of Ga 3d, Mn 2p, and As 3d core levels, with results in excellent agreement with element-projected Bloch spectral functions and clarification of the electronic structure of this prototypical material. This technique should be broadly applicable to other multi-element materials.
稀磁半导体由于其在室温下可能具有铁磁有序以及各种独特的开关和自旋相关的电导率特性，在基于自旋的电子学应用中具有前景。然而，过渡金属掺杂产生铁磁性的确切机制一直存在争议。在这里，我们使用布拉格反射驻波硬 X 射线角分辨光电子能谱研究了一种稀磁半导体（5%锰掺杂砷化镓），并将其电子结构分解为元素和动量分辨的分量。使用类似的 Ga 3d、Mn 2p 和 As 3d 芯能级的能量扫描，将测量的价带强度投影到元素分辨的分量中，结果与元素投影的 Bloch 谱函数非常吻合，并阐明了这种典型材料的电子结构。这项技术应该广泛适用于其他多元素材料。
