Spin Thermoelectric Effects in Transport through a Two-Level Quantum Dot Coupled to Ferromagnetic Leads

• Authors: Ł. Karwacki , P. Trocha , J. Barnaś
• Languages of publication: EN

Abstracts

EN

We investigate spin thermoelectric effects in a two-level quantum dot attached to external ferromagnetic leads. The basic thermoelectric coefficients are calculated by means of the non-equilibrium Green functions approach in the mean field approximation for the Coulomb term. Specifically, we calculate spin-dependent thermopower (spin Seebeck coefficient) and the charge thermopower. These coefficients measure spin and charge voltage drops across the device, respectively. Moreover, the figure of merit and its spin analog (which measures the spin thermoelectric efficiency) are presented and discussed. We also show that the indirect (via the leads) coupling between the dot's levels can significantly enhance the thermoelectric effects.

Keywords

EN

73.21.La; 73.23.-b; 73.63.Kv; 73.50.Lw

Discipline

• 73.50.Lw: Thermoelectric effects
• 73.23.-b: Electronic transport in mesoscopic systems
• 73.21.La: Quantum dots
• 73.63.Kv: Quantum dots

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2012
• Volume: 121
• Issue: 5-6
• Pages: 1207-1209

Dates

published

2012-05

Contributors

author

Ł. Karwacki

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

author

P. Trocha

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

author

J. Barnaś

• Department of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland
• Institute of Molecular Physics, Polish Academy of Sciences, M. Smoluchowskiego 17, 60-179 Poznań, Poland

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Identifiers

DOI

10.12693/APhysPolA.121.1207