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Applied Nanoscience

, Volume 9, Issue 8, pp 1685–1693 | Cite as

Tunable spin-polarized transport through a side-gated double quantum dot molecular junction in the Coulomb blockade regime

  • Yebin Dai
  • Xue-Feng WangEmail author
  • P. Vasilopoulos
  • Yu-Shen Liu
Original Article
  • 78 Downloads

Abstract

Based on nonequilibrium Green’s function method, we investigate spin-polarized transport properties of a side-gated double quantum dot (DQD) system in the Coulomb blockade regime under a magnetic field and an electric or thermal bias. The charge and spin currents oscillate frequently and can change sign upon varying gate voltage \({V_{\text{G}}}\) if the electric bias is spin–dependent. Under a thermal bias, besides the charge- and spin-current oscillations with \({V_{\text{G}}}\), a pure spin current appears at the electron–hole symmetry point. Importantly, its sign can be controlled by the magnetic field above a “critical” strength. In addition, the charge- and spin-Seebeck coefficients oscillate nontrivially depending on \({V_{\text{G}}}\), \(B\), and the tunnel coupling. Finally, we also study the spin-polarized transport properties of the DQD system effects under simultaneously applying an electric and a thermal bias.

Keywords

Double quantum dots Electric and thermal bias Charge and spin currents Coulomb blockade Charge- and spin-Seebeck coefficients 

Notes

Acknowledgements

This work was supported by National Natural Science Foundation of China (Grant Nos 61674110 and 91121021 and 6167204) and by the Canadian NSERC Grant No. OGP0121756.

Compliance with ethical standards

Conflict of interest

None of the authors of this manuscript have any competing interests.

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Copyright information

© King Abdulaziz City for Science and Technology 2019

Authors and Affiliations

  1. 1.School of Physical Science and TechnologySoochow UniversitySuzhouChina
  2. 2.Department of PhysicsConcordia UniversityMontrealCanada
  3. 3.College of Physics and Electronic EngineeringChangshu Institute of TechnologyChangshuChina

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