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Thermoelectric properties of superlattice materials with variably spaced layers

Published online by Cambridge University Press:  29 July 2011

T.D. Musho  and
D.G. Walker
T.D. Musho*
Affiliation:
Interdisciplinary Materials Science, Vanderbilt University, Nashville, Tennessee 37212
D.G. Walker*
Affiliation:
Department of Mechanical Engineering, Vanderbilt University, Nashville, Tennessee 37212
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Variably spaced semiconductor superlattices (VSSLs) exhibited superior electron mobility and rectification because of electronic level alignment. We investigated the thermoelectric properties of VSSL structures using a self-consistent nonequilibrium Green’s function quantum model to capture the ballistic electron transport and anatomistic nonequilibrium Green’s function model to capture the phonon transport. A figure of merit was calculated as a function of temperature for two VSSL strain silicon–germanium materials and a non-VSSL material. Calculation of the figure of merit (ZT) versus temperature for a VSSL demonstrated a 17 times increase in power factor at the expense of a 4 times increase in thermal conductivity at room temperature compared to a comparable uniform superlattice. Calculation determined a ZT of 0.20 for a VSSL compared to a ZT of 0.04 for non-VSSL material at 400 K. VSSLs proved to be a candidate material to further increased ZT near room temperature for superlattice materials.

Keywords

simulationthermal conductivitythermoelectric
Type
Articles
Information
Journal of Materials Research , Volume 26 , Issue 15: Focus Issue: Advances in Thermoelectric Materials , 14 August 2011 , pp. 1993 - 2000
Copyright
Copyright © Materials Research Society 2011

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References

REFERENCES

1.O’Dwyer, M.F., Lewis, R.A., Zhang, C., and Humphrey, T.E.: Electronic efficiency in nanostructured thermionic and thermoelectric devices. Phys. Rev. B 72, 205330 (2005).CrossRefGoogle Scholar
2.Summers, C.J. and Brennan, K.F.: Variably spaced superlattice energy filter, a new device design concept for high-energy electron injection. Appl. Phys. Lett. 48, 806–808 (1986).CrossRefGoogle Scholar
3.Humphrey, T.E. and Linke, H.: Reversible thermoelectric nanomaterials. Phys. Rev. Lett. 94, 096601 (2005).CrossRefGoogle ScholarPubMed
4.Bulusu, A. and Walker, D.G.: One-dimensional thin-film phonon transport with generation. Microelectron. J. 39, 950–956 (2008).CrossRefGoogle Scholar
5.Bulusu, A. and Walker, D.G.: Quantum modeling of thermoelectric performance of strained Si/Ge/Si superlattices using the nonequilibrium Green’s function method. J. Appl. Phys. 102, 073713 (2007).CrossRefGoogle Scholar
6.Zhang, W., Fisher, T.S., and Mingo, N.: The atomistic Green’s function method: An efficient simulation approach for nanoscale phonon transport. Numer. Heat Transfer 51B, 333–349 (2007).CrossRefGoogle Scholar
7.Hopkins, P.E., Norris, P.M., Tsegaye, M.S., and Ghosh, A.W.: Extracting phonon thermal conductance across atomic junctions: Nonequilibrium Green’s function approach compared to semiclassical methods. J. Appl. Phys. 106, 063503 (2009).CrossRefGoogle Scholar
8.Murphy-Armando, F. and Fahy, S.: First-principles calculation of carrier-phonon scattering in n-type Si 1−xGex alloys. Phys. Rev. B 78, 035202 (2008).CrossRefGoogle Scholar
9.Liu, P.Q., Hoffman, A.J., Escarra, M.D., Franz, K.J., Khurgin, J.B., Dikmelik, Y., Wang, X., Fan, J-Y., and Gmachl, C.F.: Highly power-efficient quantum cascade lasers. Nat. Photon 4, 95 (2010).CrossRefGoogle Scholar
10.Bai, Y., Slivken, S., Kuboya, S., Darvish, S.R., and Razeghi, M.: Quantum cascade lasers that emit more light than heat. Nat. Photon 4, 99 (2010).CrossRefGoogle Scholar
11.Escarra, M., Benz, A., Bhatt, A., Hoffman, A., Wang, X., Fan, J.-Y., and Gmachl, C.: Thermoelectric effect in quantum cascade lasers. Photon. J. IEEE 2, 500–509 (2010).CrossRefGoogle Scholar
12.Evans, A., Yu, J.S., David, J., Doris, L., Mi, K., Slivken, S., and Razeghi, M.: High-temperature, high-power, continuous-wave operation of buried heterostructure quantum-cascade lasers. Appl. Phys. Lett. 84, 314–316 (2004).CrossRefGoogle Scholar
13.Datta, S.: Quantum transport: Atom to transistor (Cambridge University Press, New York, 2005).CrossRefGoogle Scholar
14.Van de Walle, C.G.: Band lineups and deformation potentials in the model-solid theory. Phys. Rev. B 39, 1871–1883 (1989).CrossRefGoogle Scholar
15.Krishnamurthy, S., Sher, A., and Chen, A.-B.: Band structures of SixGe 1−x alloys. Phys. Rev. B 33, 1026–1035 (1986).CrossRefGoogle ScholarPubMed
16.Kittel, C.: Introduction to solid state physics, 6th ed. (Wiley, New York, 1986).Google Scholar
17.Harrison, W.: Electronic structure and the properties of solids (W.H. Freeman and Company, New York, 1989).Google Scholar