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Tuning the Non-local Spin-Spin Interaction between Quantum Dots with a Magnetic Field

Gonzalo Usaj·P. Lustemberg·C. A. Balseiro
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Abstract

We describe a device where the non-local spin-spin interaction between two quantum dots can be turned on and off and even changed sign with a very small magnetic field. The setup consists of two quantum dots at the edge of two two-dimensional electron gases (2DEGs). The quantum dots' spins are coupled through a RKKY-like interaction mediated by the electrons in the 2DEGs. A small magnetic field perpendicular to the plane of the 2DEG is used as a tuning parameter. When the cyclotron radius is commensurate with the interdot distance, the spin-spin interaction is amplified by a few orders of magnitude. The sign of the interaction is controlled by finely tuning the magnetic field. Our setup allows for several dots to be coupled in a linear arrangement and it is not restricted to nearest-neighbors interaction.

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Gonzalo Usaj, P. Lustemberg, C. A. Balseiro. 2005-02-17. Tuning the Non-local Spin-Spin Interaction between Quantum Dots with a Magnetic Field. https://doi.org/10.1103/physrevlett.94.036803

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