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Updated: Jun 21, 2026

Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
Charge sensing and controllable tunnel coupling in a Si/SiGe double quantum dot
C B Simmons1, Madhu Thalakulam, B M Rosemeyer
1University of Wisconsin-Madison, Madison, Wisconsin 53706, USA. cbsimmons@wisc.edu
Abstract:
We report integrated charge sensing measurements on a Si/SiGe double quantum dot. The quantum dot is shown to be tunable from a single, large dot to a well-isolated double dot. Charge sensing measurements enable the extraction of the tunnel coupling t between the quantum dots as a function of the voltage on the top gates defining the device. Control of the voltage on a single such gate tunes the barrier separating the two dots. The measured tunnel coupling is an exponential function of the gate voltage. The ability to control t is an important step toward controlling spin qubits in silicon quantum dots.
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