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Title: Coherent thermoelectric transport in single, double, and U-bend structures

Abstract

Coherent, i.e., ballistic, thermoelectric transport in electron waveguide structures containing right-angle bends in single, double, and U-bend configurations is investigated. A theory based on Green's functions is used to derive the transmission function (and from that the transport coefficients) and allows for the inclusion of realistic models of spatially distributed imperfections. The results for the single and double-bend structures are presented in more detail than elsewhere in the literature. In the U-bend structure, sharp resonances in the stop-band region of the transmission function lead to large-magnitude peaks in the thermopower and consequently a large thermoelectric figure of merit (of order ten in some instances). These properties are still readily apparent even in the presence of moderate edge roughness or Anderson disorder.

Authors:
; ;  [1]
  1. Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey GU2 7XH (United Kingdom)
Publication Date:
OSTI Identifier:
22413103
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ELECTRONS; GREEN FUNCTION; PERFORMANCE; RESONANCE; ROUGHNESS; THERMOELECTRIC PROPERTIES; THERMOELECTRICITY; WAVEGUIDES

Citation Formats

Pye, A. J., Faux, D. A., and Kearney, M. J. Coherent thermoelectric transport in single, double, and U-bend structures. United States: N. p., 2015. Web. doi:10.1063/1.4907911.
Pye, A. J., Faux, D. A., & Kearney, M. J. Coherent thermoelectric transport in single, double, and U-bend structures. United States. doi:10.1063/1.4907911.
Pye, A. J., Faux, D. A., and Kearney, M. J. Sat . "Coherent thermoelectric transport in single, double, and U-bend structures". United States. doi:10.1063/1.4907911.
@article{osti_22413103,
title = {Coherent thermoelectric transport in single, double, and U-bend structures},
author = {Pye, A. J. and Faux, D. A. and Kearney, M. J.},
abstractNote = {Coherent, i.e., ballistic, thermoelectric transport in electron waveguide structures containing right-angle bends in single, double, and U-bend configurations is investigated. A theory based on Green's functions is used to derive the transmission function (and from that the transport coefficients) and allows for the inclusion of realistic models of spatially distributed imperfections. The results for the single and double-bend structures are presented in more detail than elsewhere in the literature. In the U-bend structure, sharp resonances in the stop-band region of the transmission function lead to large-magnitude peaks in the thermopower and consequently a large thermoelectric figure of merit (of order ten in some instances). These properties are still readily apparent even in the presence of moderate edge roughness or Anderson disorder.},
doi = {10.1063/1.4907911},
journal = {Journal of Applied Physics},
number = 6,
volume = 117,
place = {United States},
year = {Sat Feb 14 00:00:00 EST 2015},
month = {Sat Feb 14 00:00:00 EST 2015}
}
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