The Magnetic Field Effects on Spin Polarization of T-Shaped Double Quantum Dots Coupled to Ferromagnetic Leads

• Authors: K. Wójcik , I. Weymann
• Languages of publication: EN

Abstracts

EN

We analyze the spin-dependent conductance and spin polarization of a double quantum dot in a T-shape configuration coupled to ferromagnetic leads in the presence of external magnetic field. The calculations are performed with the aid of the numerical renormalization group method. We show that in the antiparallel configuration, finite magnetic field can give rise to the full spin polarization of the current, which can be controlled by tuning the dots' levels. On the other hand, for parallel configuration enhanced spin polarization can be generated by an exchange field due to the presence of ferromagnetic leads and can be also tuned by changing level position or external magnetic field. The magnetic field can be thus used to improve the spin-resolved properties of the system.

Keywords

EN

73.23.Hk; 73.63.Kv; 85.75.-d

Discipline

• 73.23.Hk: Coulomb blockade; single-electron tunneling
• 73.63.Kv: Quantum dots
• 85.75.-d: Magnetoelectronics; spintronics: devices exploiting spin polarized transport or integrated magnetic fields

• Journal: Acta Physica Polonica A
• Year: 2015
• Volume: 127
• Issue: 2
• Pages: 222-224

Dates

published

2015-02

Contributors

author

K. Wójcik

• Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland

author

I. Weymann

• Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland

References

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Identifiers

DOI

10.12693/APhysPolA.127.222