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arXiv · 1706.08365

Optically and electrically controllable adatom spin-orbital dynamics in transition metal dichalcogenides

Bin Shao·Malte Schüler·Gunnar Schönhoff·Thomas Frauenheim·Gerd Czycholl·Tim O. Wehling
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Abstract

We analyze the interplay of spin-valley coupling, orbital physics and magnetic anisotropy taking place at single magnetic atoms adsorbed on semiconducting transition-metal dichalcogenides, MX$_2$ (M = Mo, W; X = S, Se). Orbital selection rules turn out to govern the kinetic exchange coupling between the adatom and charge carriers in the MX$_2$ and lead to highly orbitally dependent spin-flip scattering rates, as we illustrate for the example of transition metal adatoms with $d^9$ configuration. Our ab initio calculations suggest that $d^9$ configurations are realizable by single Co, Rh, or Ir adatoms on MoS$_2$, which additionally exhibit a sizable magnetic anisotropy. We find that the interaction of the adatom with carriers in the MX$_2$ allows to tune its behavior from a quantum regime with full Kondo screening to a regime of "Ising spintronics" where its spin-orbital moment acts as classical bit, which can be erased and written electronically and optically.

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Bin Shao, Malte Schüler, Gunnar Schönhoff, Thomas Frauenheim, Gerd Czycholl, Tim O. Wehling. 2017-06-26. Optically and electrically controllable adatom spin-orbital dynamics in transition metal dichalcogenides. https://doi.org/10.1021/acs.nanolett.7b02785

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