Experiments And Simulations On A Few-Electron Quantum Dot Circuit With Integrated Charge Read-Out
نویسندگان
چکیده
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 experimentally demonstrated. Computer simulations can map out the double dot charging diagram and show that the charge sensitivity can be significantly enhanced by improving the design of the circuit.
منابع مشابه
Tunable few-electron double quantum dots with integrated charge read-out
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 ...
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