Publications Details

Transport through an impurity tunnel coupled to a Si/SiGe quantum dot

Foote, Ryan H.; Ward, Daniel R.; Prance, J.R.; Laros, James H.; Nielsen, Erik N.; Thorgrimsson, Brandur; Savage, D.E.; Friesen, Mark; Coppersmith, S.N.; Eriksson, M.A.

Achieving controllable coupling of dopants in silicon is crucial for operating donor-based qubit devices, but it is difficult because of the small size of donor-bound electron wavefunctions. Here, we report the characterization of a quantum dot coupled to a localized electronic state and present evidence of controllable coupling between the quantum dot and the localized state. A set of measurements of transport through the device enable the determination that the most likely location of the localized state is consistent with a location in the quantum well near the edge of the quantum dot. Our results are consistent with a gate-voltage controllable tunnel coupling, which is an important building block for hybrid donor and gate-defined quantum dot devices.