Charge sensing and controllable tunnel coupling in a Si/SiGe double quantum dot

Nano Lett. 2009 Sep;9(9):3234-8. doi: 10.1021/nl9014974.

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.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Germanium / chemistry*
  • Materials Testing
  • Nanotechnology
  • Particle Size
  • Quantum Dots*
  • Silicon / chemistry*
  • Surface Properties

Substances

  • Germanium
  • Silicon