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arXiv · cond-mat/0612489

Tailoring Magnetism in Quantum Dots

Ramin M. Abolfath·Pawel Hawrylak·Igor Zutic
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Abstract

We study magnetism in magnetically doped quantum dots as a function of confining potential, particle numbers, temperature, and strength of Coulomb interactions. We explore possibility of tailoring magnetism by controlling the electron-electron Coulomb interaction, without changing the number of particles. The interplay of strong Coulomb interactions and quantum confinement leads to enhanced inhomogeneous magnetization which persist at higher temperatures than in the non-interacting case. The temperature of the onset of magnetization can be controlled by changing the number of particles as well as by modifying the quantum confinement and the strength of Coulomb interactions. We predict a series of electronic spin transitions which arise from the competition between the many-body gap and magnetic thermal fluctuations.

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Ramin M. Abolfath, Pawel Hawrylak, Igor Zutic. 2006-12-19. Tailoring Magnetism in Quantum Dots. https://doi.org/10.1103/physrevlett.98.207203

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