Orbital pathways for Mn2+-carriersp−dexchange in diluted magnetic semiconductor quantum dots

Abstract

Abstract. Manganese-carrier magnetic exchange interactions in strongly quantum confined -conduction-band-electron interaction is described well using the recently proposed ferromagnetic kinetic s-s exchange pathway. Antiferromagnetic kinetic s-d exchange interactions previously proposed to become dominant in quantum confined diluted magnetic semiconductors (DMSs) have been evaluated quantitatively by both DFT and perturbation theory and are found to be weak compared to the ferromagnetic s-s interaction, even in these strongly confined QDs. The magnitudes of the mean-field exchange parameters are found to be nearly independent of quantum confinement over this range of QD diameters, and the dominant orbital pathways are not fundamentally altered by quantum confinement.i.

Pulsed laser deposition of Mn doped CdSe quantum dots for improved solar cell performance

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Ferromagnetic excited-state Mn2+dimers in Zn1−xMnxSe quantum dots observed by time-resolved magnetophotoluminescence

“…Energies and electronic structures were obtained by solving the Kohn-Sham equations self-consistently using the PBE1PBE hybrid functional potential [47][48][49] with the LanL2DZ basis set [50,51], in which core electrons are replaced by an effective core and only Zn 2+ (4s, 3d, 4p), Se 2− (4s, 4p), Mn 2+ (3s, 3p, 4s, 3d), and H (1s) atomic orbitals are described with explicit basis functions. This computational scheme has been successful in describing the electronic structures of Zn 1−x T M x O (where TM = Co 2+ , Mn 2+ ) [43,52,53], Cd 1−x Mn x S [54], and Cd 1−x Mn x Se [55] nanocrystals. Convergence to the correct spin configuration was determined by analysis of the Mulliken spin density on each of the Mn 2+ dopants.…”

Quantum confinement effects on optical transitions in nanodiamonds containing nitrogen vacancies

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