title: Magnetism in closed-shell quantum dots: emergence of magnetic bipolarons.
abstract: Similar to atoms and nuclei, semiconductor quantum dots exhibit the 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.
authors.affiliation: Department of Physics, University at Buffalo, Buffalo, New York 14260-1500, USA.
authors.forename: Rafał
authors.initials: R
authors.lastname: Oszwałdowski
authors.forename: Igor
authors.initials: I
authors.lastname: Zutić
authors.forename: A G
authors.initials: AG
authors.lastname: Petukhov