Modeselected heat flow through a onedimensional waveguide network
Abstract
Crosscorrelated measurements of thermal noise are performed to determine the electron temperature in nanopatterned channels of a GaAs/AlGaAs heterostructure at 4.2 K. Twodimensional (2D) electron reservoirs are connected via an extended onedimensional (1D) electron waveguide network. Hot electrons are produced using a current I{sub h} in a source 2D reservoir, are transmitted through the ballistic 1D waveguide, and relax in a drain 2D reservoir. We find that the electron temperature increase, ΔT{sub e}, in the drain is proportional to the square of the heating current I{sub h}, as expected from Joule's law. No temperature increase is observed in the drain when the 1D waveguide does not transmit electrons. Therefore, we conclude that electronphonon interaction is negligible for heat transport between 2D reservoirs at temperatures below 4.2 K. Furthermore, mode control of the 1D electron waveguide by application of a topgate voltage reveals that ΔT{sub e} is not proportional to the number of populated subbands N, as previously observed in single 1D conductors. This can be explained with the splitting of the heat flow in the 1D waveguide network.
 Authors:
 Novel Materials Group, HumboldtUniversität zu Berlin, 12489 Berlin (Germany)
 Angewandte Festkörperphysik, RuhrUniversität Bochum, 44780 Bochum (Germany)
 (Germany)
 Publication Date:
 OSTI Identifier:
 22412714
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 8; Other Information: (c) 2015 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; ALUMINIUM ARSENIDES; ELECTRIC POTENTIAL; ELECTRON TEMPERATURE; ELECTRONPHONON COUPLING; ELECTRONS; GALLIUM ARSENIDES; HEAT FLUX; HEAT TRANSFER; HEATING; HETEROJUNCTIONS; MODE CONTROL; ONEDIMENSIONAL CALCULATIONS; TWODIMENSIONAL SYSTEMS
Citation Formats
Riha, Christian, Email: riha@physik.huberlin.de, Miechowski, Philipp, Buchholz, Sven S., Chiatti, Olivio, Fischer, Saskia F., Wieck, Andreas D., Reuter, Dirk, and Optoelektronische Materialien und Bauelemente, Universität Paderborn, 33098 Paderborn. Modeselected heat flow through a onedimensional waveguide network. United States: N. p., 2015.
Web. doi:10.1063/1.4908052.
Riha, Christian, Email: riha@physik.huberlin.de, Miechowski, Philipp, Buchholz, Sven S., Chiatti, Olivio, Fischer, Saskia F., Wieck, Andreas D., Reuter, Dirk, & Optoelektronische Materialien und Bauelemente, Universität Paderborn, 33098 Paderborn. Modeselected heat flow through a onedimensional waveguide network. United States. doi:10.1063/1.4908052.
Riha, Christian, Email: riha@physik.huberlin.de, Miechowski, Philipp, Buchholz, Sven S., Chiatti, Olivio, Fischer, Saskia F., Wieck, Andreas D., Reuter, Dirk, and Optoelektronische Materialien und Bauelemente, Universität Paderborn, 33098 Paderborn. 2015.
"Modeselected heat flow through a onedimensional waveguide network". United States.
doi:10.1063/1.4908052.
@article{osti_22412714,
title = {Modeselected heat flow through a onedimensional waveguide network},
author = {Riha, Christian, Email: riha@physik.huberlin.de and Miechowski, Philipp and Buchholz, Sven S. and Chiatti, Olivio and Fischer, Saskia F. and Wieck, Andreas D. and Reuter, Dirk and Optoelektronische Materialien und Bauelemente, Universität Paderborn, 33098 Paderborn},
abstractNote = {Crosscorrelated measurements of thermal noise are performed to determine the electron temperature in nanopatterned channels of a GaAs/AlGaAs heterostructure at 4.2 K. Twodimensional (2D) electron reservoirs are connected via an extended onedimensional (1D) electron waveguide network. Hot electrons are produced using a current I{sub h} in a source 2D reservoir, are transmitted through the ballistic 1D waveguide, and relax in a drain 2D reservoir. We find that the electron temperature increase, ΔT{sub e}, in the drain is proportional to the square of the heating current I{sub h}, as expected from Joule's law. No temperature increase is observed in the drain when the 1D waveguide does not transmit electrons. Therefore, we conclude that electronphonon interaction is negligible for heat transport between 2D reservoirs at temperatures below 4.2 K. Furthermore, mode control of the 1D electron waveguide by application of a topgate voltage reveals that ΔT{sub e} is not proportional to the number of populated subbands N, as previously observed in single 1D conductors. This can be explained with the splitting of the heat flow in the 1D waveguide network.},
doi = {10.1063/1.4908052},
journal = {Applied Physics Letters},
number = 8,
volume = 106,
place = {United States},
year = 2015,
month = 2
}

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