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Observation of low-lying excitations of electrons in coupled quantum dots

Cesar Pascual Garcia·Sokratis Kalliakos·Vittorio Pellegrini·Aron Pinczuck·Brian S. Dennis·Loren N. Pfeiffer·Ken W. West
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Abstract

Tunneling excitations of electrons in dry-etched modulation-doped AlGaAs/GaAs coupled quantum dots (QDs) are probed by resonant inelastic light scattering. A sequence of intra- and intershell excitations are found at energies determined by the interplay between the QD confinement energy $\hbar ω_0$ and the tunneling gap $Δ_{SAS}$, the splitting between the symmetric and anti-symmetric delocalized single particle molecular states. The narrow line-widths displayed by electronic excitations in these nanostructures indicate promising venues for the spectroscopic investigation of entanglement of electron states in these artificial molecules.

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Cesar Pascual Garcia, Sokratis Kalliakos, Vittorio Pellegrini, Aron Pinczuck, Brian S. Dennis, Loren N. Pfeiffer, Ken W. West. 2005-11-23. Observation of low-lying excitations of electrons in coupled quantum dots. https://doi.org/10.1063/1.2185447

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