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arXiv · 0907.4726

Para-ortho transition of artificial H$_2$ molecule in lateral quantum dots doped with magnetic impurities

Ramin M. Abolfath
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Abstract

We present the magnetic phase diagram of artificial H$_2$ molecule in lateral quantum dots doped with magnetic impurities as a function of external magnetic field and plunger gate voltage. The onset of Mn-Mn antiferromagnetic-ferromagnetic transition follows the electron spin singlet-triplet transition. We deploy a configuration-interaction method to exactly diagonalize the electron-Mn Hamiltonian and map it to an effective Mn-Mn Heisenberg Hamiltonian. We find that Mn-Mn exchange coupling can be described by RKKY-interaction/magnetic-polaron in weak/strong electron-Mn coupling at low/high magnetic fields.

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Ramin M. Abolfath. 2009-07-27. Para-ortho transition of artificial H$_2$ molecule in lateral quantum dots doped with magnetic impurities. https://doi.org/10.1103/physrevb.80.165332

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