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arXiv · 1706.00104

Spin-Seebeck effect and spin polarization in a multiple quantum dot molecule

J. P. Ramos-Andrade·F. J. Peña·A. González·O. Ávalos-Ovando·P. A. Orellana
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Abstract

In this work, we study the conductance and the thermoelectric properties of a quantum dot embedded between two metallic leads with a side-coupled triple quantum dot molecule under a magnetic field. We focus on the spin polarization and thermoelectric quantities. Our results show the possibility of design an efficient spin filter device besides a noticeable enhancement of the Seebeck coefficient driven by the asymmetry in the quantum dots energy levels and a tunable pure spin Seebeck effect is obtained. This behavior also holds in the interacting case, where a pure spin Seebeck effect can be obtained for fixed values of the embedded quantum dot energy level. Our findings could lead to the implementation of a new pure spin energy conversion and capable spin filter devices working with weak magnetic fields.

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J. P. Ramos-Andrade, F. J. Peña, A. González, O. Ávalos-Ovando, P. A. Orellana. 2017-10-13. Spin-Seebeck effect and spin polarization in a multiple quantum dot molecule. https://doi.org/10.1103/physrevb.96.165413

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