Spin-Polarized Transport through Quantum Dots in the Cotunneling Regime

• Authors: I. Weymann
• Languages of publication: EN

Abstracts

EN

The spin-polarized transport through two-level quantum dots weakly coupled to ferromagnetic leads is considered theoretically in the Coulomb blockade regime. It is assumed that the dot is doubly occupied, so that the current flows due to cotunneling through singlet and triplet states of the dot. It is shown that, by sweeping the bias voltage, one can induce a singlet-triplet transition, which depends on the magnetic configuration of the system and leads to nontrivial bias dependence of both the differential conductance and tunnel magnetoresistance.

Keywords

EN

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

Discipline

• 73.23.Hk: Coulomb blockade; single-electron tunneling
• 72.25.Mk: Spin transport through interfaces
• 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: 2008
• Volume: 113
• Issue: 1
• Pages: 529-532

Dates

published

2008-01

received

2007-07-09

Contributors

author

I. Weymann

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

References

• 1. S. Maekawa, T. Shinjo, Spin Dependent Transport in Magnetic Nanostructures, Taylor Francis, London 2002
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• 3. I. Weymann, J. König, J. Martinek, J. Barnaś, G. Schön, Phys. Rev. B 72, 115334 (2005); I. Weymann, Europhys. Lett. 76, 1200 (2006); I. Weymann, J. Barnaś, Phys. Rev. B 75, 155308 (2007)
• 4. W. Izumida, O. Sakai, S. Tarucha, Phys. Rev. Lett. 87, 216803 (2001)
• 5. M. Julliere, Phys. Lett. A 54, 225 (1975)

Identifiers

DOI

10.12693/APhysPolA.113.529