Thermopower as a tool to investigate manybody 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 manybody quantum effects, which is less intrusive than the usual chargestability diagram as no high sourcedrain 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:
 Nanometer Structure Consortium (nmCLU), Lund University, Box 118, 22100 Lund (Sweden)
 (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; MANYBODY PROBLEM; SIMULATION; SPECTRA; SPECTROSCOPY; STABILITY; THERMODYNAMIC PROPERTIES
Citation Formats
Kristinsdóttir, L. H., Bengtsson, J., Reimann, S. M., Wacker, A., Email: 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 manybody 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., Email: 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 manybody effects in quantum systems. United States. doi:10.1063/1.4893928.
Kristinsdóttir, L. H., Bengtsson, J., Reimann, S. M., Wacker, A., Email: 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 manybody effects in quantum systems". United States.
doi:10.1063/1.4893928.
@article{osti_22310968,
title = {Thermopower as a tool to investigate manybody effects in quantum systems},
author = {Kristinsdóttir, L. H. and Bengtsson, J. and Reimann, S. M. and Wacker, A., Email: 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 manybody quantum effects, which is less intrusive than the usual chargestability diagram as no high sourcedrain 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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