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2021.0720

The Discovery of Diluted Magnetic Material from Prof. Liu Yi Hsin Published on International Journal

Wireless communication technology is regarded as the emerging, focus of the future encryption communication technology roadmap, attracting countries to invest in the research and development of quantum materials. After five years of research and experiments, the lab of Assistant Professor at the Department of Chemistry Liu Yi Hsin proposed to use organic-inorganic semiconductor materials to introduce manganese ions through solvothermal method to synthesize atomic-level two-dimensional single-layer semiconductors, which at room temperature, can demonstrate strong Giant Zeeman splitting and zero-field splitting at extremely low temperatures.

The atomic-level doping technology in this diluted magnetic material enables the material to have a long luminescence cycle, which has the opportunity to realize the application of quantum electrodynamics and single quantum dot light emitters, and this is crucial development of the chemical synthesis of quantum materials. The paper is published on the Journal of the American Chemical Society.

The abstract of the paper is as follows:

Giant Zeeman splitting and zero-field splitting (ZFS) are observed in 2D nanosheets that have monolayers of atomic thickness. In this study, single-crystalline CdSe(ethylenediamine)0.5 and Mn2+-doped nanosheets are synthesized via a solvothermal process. Tunable amounts of Mn2+(0.5–8.0%) are introduced, resulting in lattice contraction as well as phosphorescence from five unpaired electrons. The exciton dynamics are dominated by spin-related electronic transitions (4T1 → 6A1) with long lifetimes (20.5, 132, and 295 μs). Temperature-varied EPR spectroscopy with spectral simulation reveals large ZFS (D = 3850 MHz) due to axial distortion of substituted Mn2+ (S = 5/2). In the magnetic circular dichroism (MCD) measurements, we observed giant Zeeman splitting with large effective g values (up to 231 ± 21), which implies huge sp–d exchange interactions in 2D monolayer regimes, leading to diluted magnetic semiconductor (DMS) materials.