Confined free-electrons in an applied electric field: Discontinuous electron density

Stephane Pleutin

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arXiv · cond-mat/0412600

Confined free-electrons in an applied electric field: Discontinuous electron density

Stephane Pleutin

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Abstract

We consider free electrons in rectangular quantum dots, with either hard wall boundary conditions or anharmonic confinement. In both cases, due to finite size effects, a homogeneous electric field applied along one of the rectangular axis is shown to induce abrupt changes in the electron density, parallel and perpendicularly to the field direction: the electron density jumps from one configuration to another. Making use of this property, we propose a purely electrical mechanism to control the magnitude of the effective exchange coupling between two quantum dots. This system has been proposed recently as a quantum gate for quantum computation.

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Stephane Pleutin. 2004-12-22. Confined free-electrons in an applied electric field: Discontinuous electron density. https://arxiv.org/abs/cond-mat/0412600

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