Resonant inelastic light scattering provides a venue for the study of spin transitions and interactions in quantum dots (QDs) with few electrons. Here we present the observation of inter-shell excitations in GaAs/AlGaAs nanofabricated QDs containing four electrons. The ground state with four electrons dictated by Hund's rule is a triplet with total spin S = 1 so that peculiar to this configuration there are two monopole inter-shell spin modes with changes ΔS = ±1 that connect the triplet state to the excited states with S = 0 and S = 2, respectively. We present light scattering spectra that offer evidence of these excitations. The light scattering spectra are interpreted by numerical evaluations within a full configuration interaction approach. © 2007 American Institute of Physics.
Probing spin states in AlGaAs/GaAs few-electron quantum dots by inelastic light scattering / Kalliakos, S.; Pascual Garcia, C.; Pellegrini, V.; Pinczuk, A.; Dennis, B. S.; Pfeiffer, L. N.; West, K. W.; Rontani, M.; Goldoni, G.; Molinari, E.. - In: AIP CONFERENCE PROCEEDINGS. - ISSN 0094-243X. - 893:(2007), pp. 959-960. (Intervento presentato al convegno 28th International Conference on the Physics of Semiconductors, ICPS 2006 tenutosi a Vienna, aut nel 2006) [10.1063/1.2730212].