The influence of non-idealities on the thermoelectric power factor of nanostructured superlattices

@article{Thesberg2015TheIO,
  title={The influence of non-idealities on the thermoelectric power factor of nanostructured superlattices},
  author={Mischa Thesberg and Mahdi Pourfath and Hans Kosina and Neophytos Neophytou},
  journal={arXiv: Materials Science},
  year={2015}
}
Cross-plane superlattices composed of nanoscale layers of alternating potential wells and barriers have attracted great attention for their potential to provide thermoelectric power factor improvements and higher ZT figure of merit. Previous theoretical works have shown that the presence of optimized potential barriers could provide improvements to the Seebeck coefficient through carrier energy filtering, which improves the power factor by up to 40%. However, experimental corroboration of this… 

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References

SHOWING 1-10 OF 41 REFERENCES

Optimizing thermoelectric power factor by means of a potential barrier

Large efforts in improving thermoelectric energy conversion are devoted to energy filtering by nanometer size potential barriers. In this work, we perform an analysis and optimization of such

Gated Si nanowires for large thermoelectric power factors

We investigate the effect of electrostatic gating on the thermoelectric power factor of p-type Si nanowires (NWs) of up to 20 nm in diameter in the [100], [110], and [111] crystallographic transport

Computational study of energy filtering effects in one-dimensional composite nano-structures

Possibilities to improve the Seebeck coefficient S versus electrical conductance G trade-off of diffusive composite nano-structures are explored using an electro-thermal simulation framework based on

Silicon nanowires as efficient thermoelectric materials

Independent measurements of the Seebeck coefficient, the electrical conductivity and the thermal conductivity, combined with theory, indicate that the improved efficiency originates from phonon effects, and these results are expected to apply to other classes of semiconductor nanomaterials.

Simultaneous increase in electrical conductivity and Seebeck coefficient in highly boron-doped nanocrystalline Si

It is shown that transport takes place through two phases so that high conductivity is achieved in the grains, and high Seebeck coefficient by the grain boundaries, which together with the drastic reduction in the thermal conductivity due to boundary scattering could lead to a significant increase of the figure of merit ZT.

Computational study of the Seebeck coefficient of one-dimensional composite nano-structures

The Seebeck coefficient (S) of composite nano-structures is theoretically explored within a self-consistent electro-thermal transport simulation framework using the non-equilibrium Green’s function

Field-effect modulation of thermoelectric properties in multigated silicon nanowires.

This work fabricates multigated silicon nanowires (Si NWs) and demonstrates significant modulation of electrical conductivity and the Seebeck coefficient with gate bias, demonstrating that power factor for the gated Si NWs is similar to the highest values reported for n-type Si nanostructures despite charge transport only occurring at the NW surface.

Enhancing the thermoelectric figure of merit through the reduction of bipolar thermal conductivity with heterostructure barriers

In this paper, we present theoretically that the thermoelectric figure of merit for a semiconductor material with a small band gap can be significantly enhanced near the intrinsic doping regime at

Si/Ge superlattice nanowires with ultralow thermal conductivity.

Two competing mechanisms governing the thermal transport in superlattice nanowires are identified, responsible for this nonmonotonic behavior: interface modulation in the longitudinal direction significantly depressing the phonon group velocities and hindering heat conduction, and coherent phonons occurring at extremely short periodic lengths counteracting the interface effect and facilitating thermal transport.

Improved thermoelectric power factor in metal-based superlattices.

It is shown that metal-based superlattices with tall barriers can achieve a large effective thermoelectric figure of merit (ZT > 5 at room temperature), a key parameter to achieving high performance is the nonconservation of lateral momentum during the thermionic emission process.