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arXiv · 1801.06587

Element- and momentum-resolved electronic structure of the dilute magnetic semiconductor manganese doped gallium arsenide

Slavomír Nemšák·Mathias Gehlmann·Cheng-Tai Kuo·Shih-Chieh Lin·Christoph Schlueter·Ewa Mlynczak·Tien-Lin Lee·Lukasz Plucinski·Hubert Ebert·Igor Di Marco·Ján Minár·Claus M. Schneider·Charles S. Fadley
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Abstract

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.

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Slavomír Nemšák, Mathias Gehlmann, Cheng-Tai Kuo, Shih-Chieh Lin, Christoph Schlueter, Ewa Mlynczak, Tien-Lin Lee, Lukasz Plucinski, Hubert Ebert, Igor Di Marco, Ján Minár, Claus M. Schneider, Charles S. Fadley. 2018-09-12. Element- and momentum-resolved electronic structure of the dilute magnetic semiconductor manganese doped gallium arsenide. https://doi.org/10.1038/s41467-018-05823-z

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