Applied Physics Letters · 2000 · 111 citations · 14 references
Natural SciencesMaterials SciencePhysicsCondensed Matter PhysicsOptoelectronicsSemiconductor MaterialsNanoelectronicsQuantum DotsQuantum OptoelectronicsQuantum TunnelingSemiconductor PhysicsWide Band Gap SemiconductorsActivation EnergyExcited Electronic StatesExcited StatesSemiconductor Quantum DotsThermal ActivationTime ConstantTunneling PhenomenaValence Band
Carrier escape processes from self-organized InAs quantum dots QDs embedded in GaAs are investigated by time-resolved capacitance spectroscopy. Electron emission is found to be dominated by tunneling processes. In addition to tunneling from the ground state, we find thermally activated tunneling involving excited QD states with an activation energy of 82 meV. For holes, the tunnel contribution is negligible and thermal activation from the QD ground state to the GaAs valence band with an activation energy of 164 meV dominates. Extrapolation to room temperature yields an emission time constant of 5 ps for holes, which is an order of magnitude larger than for electrons. The measured activation energies agree well with theoretically predicted QD levels.
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Spectroscopy of Quantum Levels in Charge-Tunable InGaAs Quantum Dots
Hedda Drexler, D. Leonard, W. Hansen et al. · Physical Review Letters · 1994 · 731 citations
Few-electron ground states of charge-tunable self-assembled quantum dots
Barbara Miller, W. Hansen, S. Manus et al. · Physical review. B, Condensed matter · 1997 · 244 citations