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arXiv · 1106.2346

Magnetism in Closed-shell Quantum Dots: Emergence of Magnetic Bipolarons

R. Oszwałdowski·I. Žutić·A. G. Petukhov
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Abstract

Similar to atoms and nuclei, semiconductor quantum dots exhibit formation of shells. Predictions of magnetic behavior of the dots are often based on the shell occupancies. Thus, closed-shell quantum dots are assumed to be inherently nonmagnetic. Here, we propose a possibility of magnetism in such dots doped with magnetic impurities. On the example of the system of two interacting fermions, the simplest embodiment of the closed-shell structure, we demonstrate the emergence of a novel broken-symmetry ground state that is neither spin-singlet nor spin-triplet. We propose experimental tests of our predictions and the magnetic-dot structures to perform them.

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R. Oszwałdowski, I. Žutić, A. G. Petukhov. 2011-06-12. Magnetism in Closed-shell Quantum Dots: Emergence of Magnetic Bipolarons. https://doi.org/10.1103/physrevlett.106.177201

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