Tunable few-electron double quantum dots with integrated charge read-out
نویسندگان
چکیده
We report on the realization of few-electron double quantum dots defined in a two-dimensional electron gas by means of surface gates on top of a GaAs/AlGaAs heterostructure. Two quantum point contacts (QPCs) are placed in the vicinity of the double quantum dot and serve as charge detectors. These enable determination of the number of conduction electrons on each dot. This number can be reduced to zero, while still allowing transport measurements through the double dot. The coupling between the two dots can be controlled even in the few-electron regime. Microwave radiation is used to pump an electron from one dot to the other by absorption of a single photon. The experiments demonstrate that this quantum dot circuit can serve as a good starting point for a scalable spin-qubit system. r 2004 Elsevier B.V. All rights reserved. PACS: 73.23.-b; 73.23.Hk; 73.63.Kv
منابع مشابه
Experiments And Simulations On A Few-Electron Quantum Dot Circuit With Integrated Charge Read-Out
We report measurements and simulations on a fully tunable double quantum dot circuit, integrated with two quantum point contacts that serve as charge detectors. The circuit is defined in a two-dimensional electron gas by means of surface gates on top of a GaAs/AlGaAs heterostructure. Full control over the electron number (down to zero), the dot-lead coupling and the inter-dot tunnel coupling is...
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