https://doi.org/10.1140/epjb/e2018-80552-8
Regular Article
Thermoelectric efficiency enhanced in a quantum dot with polarization leads, spin-flip and external magnetic field
1
Institute of Theoretical Physics, State Key Laboratory of Quantum Optics and Quantum Optics Devices, Shanxi University,
Taiyuan
030006, P.R. China
2
Institute of Solid State Physics, Shanxi Datong University,
Datong
037009, P.R. China
3
School of Applied Science, Taiyuan University of Science and Technology,
Taiyuan
030024, P.R. China
a e-mail: nieyh@sxu.edu.cn
Received:
30
September
2017
Received in final form:
26
January
2018
Published online: 29
March
2018
We theoretically study the thermoelectric transport properties in a quantum dot system with two ferromagnetic leads, the spin-flip scattering and the external magnetic field. The results show that the spin polarization of the leads strongly influences thermoelectric coefficients of the device. For the parallel configuration the peak of figure of merit increases with the increase of polarization strength and non-collinear configuration trends to destroy the improvement of figure of merit induced by lead polarization. While the modulation of the spin-flip scattering on the figure of merit is effective only in the absence of external magnetic field or small magnetic field. In terms of improving the thermoelectric efficiency, the external magnetic field plays a more important role than spin-flip scattering. The thermoelectric efficiency can be significantly enhanced by the magnetic field for a given spin-flip scattering strength.
Key words: Mesoscopic and Nanoscale Systems
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2018