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Title: Thermopower as a tool to investigate many-body effects in quantum systems

Abstract

Measuring the thermopower of a confined quantum system reveals important information about its excitation spectrum. Our simulations show how this kind of transport spectroscopy is able to extract a clear signal for the onset of Wigner localization in a nanowire segment. This demonstrates that thermopower measurements provide a tool for investigating complex many-body quantum effects, which is less intrusive than the usual charge-stability diagram as no high source-drain bias is required. While the effect is most pronounced for weak tunnel coupling and low temperatures, the excited states also significantly affect the thermopower spectrum at moderate temperature, adding distinct features to the characteristic thermopower lineshape.

Authors:
; ; ;  [1];  [2];  [1];  [2]
  1. Nanometer Structure Consortium (nmC-LU), Lund University, Box 118, 22100 Lund (Sweden)
  2. (Sweden)
Publication Date:
OSTI Identifier:
22310968
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; COUPLING; EXCITATION; EXCITED STATES; MANY-BODY PROBLEM; SIMULATION; SPECTRA; SPECTROSCOPY; STABILITY; THERMODYNAMIC PROPERTIES

Citation Formats

Kristinsdóttir, L. H., Bengtsson, J., Reimann, S. M., Wacker, A., E-mail: Andreas.Wacker@fysik.lu.se, Mathematical Physics, Lund University, Box 118, 22100 Lund, Linke, H., and Solid State Physics, Lund University, Box 118, 22100 Lund. Thermopower as a tool to investigate many-body effects in quantum systems. United States: N. p., 2014. Web. doi:10.1063/1.4893928.
Kristinsdóttir, L. H., Bengtsson, J., Reimann, S. M., Wacker, A., E-mail: Andreas.Wacker@fysik.lu.se, Mathematical Physics, Lund University, Box 118, 22100 Lund, Linke, H., & Solid State Physics, Lund University, Box 118, 22100 Lund. Thermopower as a tool to investigate many-body effects in quantum systems. United States. doi:10.1063/1.4893928.
Kristinsdóttir, L. H., Bengtsson, J., Reimann, S. M., Wacker, A., E-mail: Andreas.Wacker@fysik.lu.se, Mathematical Physics, Lund University, Box 118, 22100 Lund, Linke, H., and Solid State Physics, Lund University, Box 118, 22100 Lund. Mon . "Thermopower as a tool to investigate many-body effects in quantum systems". United States. doi:10.1063/1.4893928.
@article{osti_22310968,
title = {Thermopower as a tool to investigate many-body effects in quantum systems},
author = {Kristinsdóttir, L. H. and Bengtsson, J. and Reimann, S. M. and Wacker, A., E-mail: Andreas.Wacker@fysik.lu.se and Mathematical Physics, Lund University, Box 118, 22100 Lund and Linke, H. and Solid State Physics, Lund University, Box 118, 22100 Lund},
abstractNote = {Measuring the thermopower of a confined quantum system reveals important information about its excitation spectrum. Our simulations show how this kind of transport spectroscopy is able to extract a clear signal for the onset of Wigner localization in a nanowire segment. This demonstrates that thermopower measurements provide a tool for investigating complex many-body quantum effects, which is less intrusive than the usual charge-stability diagram as no high source-drain bias is required. While the effect is most pronounced for weak tunnel coupling and low temperatures, the excited states also significantly affect the thermopower spectrum at moderate temperature, adding distinct features to the characteristic thermopower lineshape.},
doi = {10.1063/1.4893928},
journal = {Applied Physics Letters},
number = 8,
volume = 105,
place = {United States},
year = {Mon Aug 25 00:00:00 EDT 2014},
month = {Mon Aug 25 00:00:00 EDT 2014}
}
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