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Quantum Confinement Suppressing Electronic Heat Flow below the Wiedemann-Franz Law.

ABSTRACT: The Wiedemann-Franz law states that the charge conductance and the electronic contribution to the heat conductance are proportional. This sets stringent constraints on efficiency bounds for thermoelectric applications, which seek a large charge conduction in response to a small heat flow. We present experiments based on a quantum dot formed inside a semiconducting InAs nanowire transistor, in which the heat conduction can be tuned significantly below the Wiedemann-Franz prediction. Comparison with scattering theory shows that this is caused by quantum confinement and the resulting energy-selective transport properties of the quantum dot. Our results open up perspectives for tailoring independently the heat and electrical conduction properties in semiconductor nanostructures.

SUBMITTER: Majidi D

PROVIDER: S-EPMC8802316 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Quantum Confinement Suppressing Electronic Heat Flow below the Wiedemann-Franz Law.

Majidi Danial D Josefsson Martin M Kumar Mukesh M Leijnse Martin M Samuelson Lars L Courtois Hervé H Winkelmann Clemens B CB Maisi Ville F VF

Nano letters 20220114 2

The Wiedemann-Franz law states that the charge conductance and the electronic contribution to the heat conductance are proportional. This sets stringent constraints on efficiency bounds for thermoelectric applications, which seek a large charge conduction in response to a small heat flow. We present experiments based on a quantum dot formed inside a semiconducting InAs nanowire transistor, in which the heat conduction can be tuned significantly below the Wiedemann-Franz prediction. Comparison wi ...[more]

PMID: 35030004

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