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arXiv · 1509.05068

Magnetic ordering in quantum dots: Open vs. closed shells

J. M. Pientka·R. Oszwałdowski·A. G. Petukhov·J. E. Han·Igor Žutić
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Abstract

In magnetically-doped quantum dots changing the carrier occupancy, from open to closed shells, leads to qualitatively different forms of carrier-mediated magnetic ordering. While it is common to study such nanoscale magnets within a mean field approximation, excluding the spin fluctuations can mask important phenomena and lead to spurious thermodynamic phase transitions in small magnetic systems. By employing coarse-grained, variational, and Monte Carlo methods on singly and doubly occupied quantum dots to include spin fluctuations, we evaluate the relevance of the mean field description and distinguish different finite-size scaling in nanoscale magnets.

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J. M. Pientka, R. Oszwałdowski, A. G. Petukhov, J. E. Han, Igor Žutić. 2015-09-16. Magnetic ordering in quantum dots: Open vs. closed shells. https://doi.org/10.1103/physrevb.92.155402

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