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Boosting spin-caloritronic effects by attractive correlations in molecular junctions
1Faculty of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznań, Poland.
Scientific Reports
|January 26, 2016
Summary
Attractive correlations in molecular junctions enhance thermoelectric performance. This study shows these correlations boost spin thermopower and figure of merit, controllable via gate voltage, for advanced thermoelectric devices.
Area of Science:
- Condensed Matter Physics
- Nanoscience
- Quantum Transport
Background:
- Quantum confinement in nanoscopic systems enhances thermoelectric properties beyond bulk materials.
- Nanostructures like molecular junctions offer potential for high thermoelectric figures of merit.
- Spin-dependent thermoelectric transport in ferromagnetic nanostructures is crucial for spintronics.
Purpose of the Study:
- To investigate spin-dependent thermoelectric transport in a molecular junction with attractive Coulomb correlations.
- To analyze the impact of attractive correlations on spin-resolved transport properties.
- To explore the potential for enhancing thermoelectric performance using attractive correlations.
Main Methods:
- Utilized the numerical renormalization group (NRG) method.
- Examined a molecular junction coupled to ferromagnetic leads.
- Focused on an orbital level with attractive Coulomb correlations.
Main Results:
- Discovered a nontrivial dependence of conductance and tunnel magnetoresistance on correlation strength and sign.
- Demonstrated that attractive correlations enhance spin thermopower.
- Showed enhancement of the thermoelectric figure of merit due to attractive correlations.
Conclusions:
- Attractive Coulomb correlations significantly influence spin-dependent thermoelectric transport in molecular junctions.
- These correlations can lead to improved spin thermopower and figure of merit.
- Gate voltage control offers a mechanism to tune these enhanced thermoelectric properties.
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