Using a two-dimensional electron gas to study nonequilibrium tunneling dynamics and charge storage in self-assembled quantum dots

Marquardt, B.; Geller, M.; Lorke, A.; Reuter, D.; Wieck, A. D.
July 2009
Applied Physics Letters;7/13/2009, Vol. 95 Issue 2, p022113
Academic Journal
We demonstrate a strong influence of charged self-assembled quantum dots (QD) on the conductance of a nearby two-dimensional electron gas (2DEG). A conductance measurement of the 2DEG allows us to probe the charge tunneling dynamics between the 2DEG and the QDs in nonequilibrium as well as close to equilibrium. Measurements of hysteresis curves with different sweep times and time-resolved conductance measurements enable us to unambiguously identify the transients as tunneling events between the 2DEG and QD states.


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