The emergence of spintronic applications has stimulated intense interest due to expectations for new functionalities and devices. However, in a I-II-V diluted magnetic semiconductor Li(Zn, Mn)As system as a corresponding material, the mechanism of the doping and ferromagnetism is not clear yet. Here, we used aberration-corrected scanning transmission electron microscopy to investigate the microstructures of the paramagnetic and ferromagnetic ${\mathrm{Li}}_{1+y}{\mathrm{Zn}}_{1–x}{\mathrm{Mn}}_x\mathrm{As}$ (nominal composition: ${\mathrm{Li}}_{1.0}{\mathrm{Zn}}_{0.9}{\mathrm{Mn}}_{0.1}{\mathrm{As}}_{1.0}$ and ${\mathrm{Li}}_{1.1}{\mathrm{Zn}}_{0.9}{\mathrm{Mn}}_{0.1}{\mathrm{As}}_{1.0}$) compounds at atomic scale. Our results provide clear evidence that superstructures exist in a diluted magnetic semiconductor. We also reveal the origin of the modulated structure of the Li(Zn, Mn)As system. With the above studies, we indicate the relationship between the structure and magnetism, and investigate the charge and spin controlling mechanism in the diluted magnetic semiconductor. Our studies may provide a way to search for diluted magnetic semiconductors with novel and excellent properties.

• Received 5 May 2020
• Revised 11 August 2020
• Accepted 27 August 2020

DOI:https://doi.org/10.1103/PhysRevMaterials.4.094412