Charge sensing and controllable tunnel coupling in a Si/SiGe double quantum dot.
/ Authors
C. Simmons, M. Thalakulam, B. Rosemeyer, B. V. Bael, E. Sackmann, D. Savage, M. Lagally, R. Joynt, M. Friesen, S. Coppersmith
and 1 more author
/ 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.
Journal: Nano letters
DOI: 10.1021/nl9014974