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Evidence of correlation in spin excitations of few-electron quantum dots

Cesar Pascual Garcia·Vittorio Pellegrini·Aron Pinczuk·Massimo Rontani·Guido Goldoni·Elisa Molinari·Brian S. Dennis·Loren N. Pfeiffer·Ken W. West
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Abstract

We report inelastic light scattering measurements of spin and charge excitations in nanofabricated AlGaAs/GaAs quantum dots with few electrons. A narrow spin excitation peak is observed and assigned to the intershell triplet-to-singlet monopole mode of dots with four electrons. Configurationinteraction theory provides precise quantitative interpretations that uncover large correlation effects that are comparable to exchange Coulomb interactions.

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Cesar Pascual Garcia, Vittorio Pellegrini, Aron Pinczuk, Massimo Rontani, Guido Goldoni, Elisa Molinari, Brian S. Dennis, Loren N. Pfeiffer, Ken W. West. 2005-09-07. Evidence of correlation in spin excitations of few-electron quantum dots. https://doi.org/10.1103/physrevlett.95.266806

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