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arXiv · 0706.3833

Spin states and persistent currents in a mesoscopic ring with an embedded magnetic impurity

J. S. Sheng·Kai Chang
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Abstract

Spin states and persistent currents are investigated theoretically in a mesoscopic ring with an embedded magnetic ion under a uniform magnetic field including the spin-orbit interactions. The magnetic impurity acts as a spin-dependent $δ$-potential for electrons and results in gaps in the energy spectrum, consequently suppresses the oscillation of the persistent currents. The competition between the Zeeman splittings and the $s$-$d$ exchange interaction leads to a transition of the electron ground state in the ring. The interplay between the periodic potential induced by the Rashba and Dresselhaus spin-orbit interactions and the $δ$-potential induced by the magnetic impurity leads to significant variation in the energy spectrum, charge density distribution, and persistent currents of electrons in the ring.

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J. S. Sheng, Kai Chang. 2007-06-26. Spin states and persistent currents in a mesoscopic ring with an embedded magnetic impurity. https://doi.org/10.1088/0953-8984%2F20%2F02%2F025222

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