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Title: Thermoelectric properties of MBE-grown HgCdTe-based superlattices from 100K to 300K

Authors:
; ORCiD logo; ORCiD logo; ; ; ORCiD logo;
Publication Date:
Research Org.:
Energy Frontier Research Centers (EFRC) (United States). Center for Solar and Thermal Energy Conversion (CSTEC)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1370114
DOE Contract Number:
SC0000957
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 7; Related Information: CSTEC partners with University of Michigan (lead); Kent State University
Country of Publication:
United States
Language:
English

Citation Formats

Zhang, Kejia, Yadav, Abhishek, Shao, Lei, Bommena, Ramana, Zhao, Jun, Velicu, Silviu, and Pipe, Kevin P. Thermoelectric properties of MBE-grown HgCdTe-based superlattices from 100K to 300K. United States: N. p., 2016. Web. doi:10.1063/1.4959159.
Zhang, Kejia, Yadav, Abhishek, Shao, Lei, Bommena, Ramana, Zhao, Jun, Velicu, Silviu, & Pipe, Kevin P. Thermoelectric properties of MBE-grown HgCdTe-based superlattices from 100K to 300K. United States. doi:10.1063/1.4959159.
Zhang, Kejia, Yadav, Abhishek, Shao, Lei, Bommena, Ramana, Zhao, Jun, Velicu, Silviu, and Pipe, Kevin P. 2016. "Thermoelectric properties of MBE-grown HgCdTe-based superlattices from 100K to 300K". United States. doi:10.1063/1.4959159.
@article{osti_1370114,
title = {Thermoelectric properties of MBE-grown HgCdTe-based superlattices from 100K to 300K},
author = {Zhang, Kejia and Yadav, Abhishek and Shao, Lei and Bommena, Ramana and Zhao, Jun and Velicu, Silviu and Pipe, Kevin P.},
abstractNote = {},
doi = {10.1063/1.4959159},
journal = {AIP Advances},
number = 7,
volume = 6,
place = {United States},
year = 2016,
month = 7
}
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  • Doping in a manner that introduces anisotropy in order to reduce thermal conductivity is a significant focus in thermoelectric research today. By solving the semiclassical Boltzmann transport equations in the constant scattering time (τ) approximation, in conjunction with ab initio electronic structure calculations, within Density Functional Theory, we compare the Seebeck coefficient (S) and figure of merit (ZT) of bulk PbTe to PbTe/SnTe/PbTe heterostructures and PbTe doping superlattices (SLs) with periodically doped planes. Bismuth and Thallium were used as the n- and p-type impurities, respectively. The effects of carrier concentration are considered via chemical potential variation in a rigid bandmore » approximation. The impurity bands near the Fermi level in the electronic structure of PbTe SLs are of Tl s- and Bi p-character, and this feature is independent of the doping concentration or the distance between impurity planes. We observe the impurity bands to have a metallic nature in the directions perpendicular to the doping planes, yet no improvement on the values of ZT is found when compared to bulk PbTe. For the PbTe/SnTe/PbTe heterostructures, the calculated S presents good agreement with recent experimental data, and an anisotropic behavior is observed for low carrier concentrations (n<10{sup 18} cm{sup −3}). A large value of ZT{sub ||} (parallel to the growth direction) of 3.0 is predicted for n=4.7×10{sup 18} cm{sup −3} and T=700 K, whereas ZT{sub p} (perpendicular to the growth direction) is found to peak at 1.5 for n=1.7×10{sup 17} cm{sup −3}. Both electrical conductivity enhancement and thermal conductivity reduction are analyzed. - Graphical abstract: Figure of merit for PbTe/SnTe/PbTe heterostructure along the [0 0 1] direction, P.D. Borges, J.E. Petersen, L. Scolfaro, H.W. Leite Alves, T.H. Myers, Improved thermoelectric properties of IV–VI-based heterostructures and superlattices. - Highlights: • Thermoelectric properties of IV–VI-based heterostructures and superlattices. • High figure of merit is predicted for the PbTe/SnTe/PbTe heterostructure. • Nanotechnology has an important role for the development of thermoelectric devices.« less