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Spontaneous spin polarized tunneling current through a quantum dot array

David M. -T. Kuo·Y. -C. Chang
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Abstract

We show theoretically that a strongly spin-polarized current can be generated in semiconductors by taking advantage of the ferromagnetic phase of a quantum dot array (QDA). A Hubbard model with coupling to leads is used to study the tunneling current of the QDA system as a function of gate voltage. Due to the weak interdot coupling and strong Coulomb repulsion, it is found that a ferromagnetic phase exists in QDA within a window of gate voltage. Therefore QDA can be used as a spin filter to detect and control spin states in quantum information devices.

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David M. -T. Kuo, Y. -C. Chang. 2002-09-20. Spontaneous spin polarized tunneling current through a quantum dot array. https://arxiv.org/abs/cond-mat/0209499

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