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تسجيل مستخدم جديدQuantum confinement suppressing electronic heat flow below the Wiedemann-Franz law
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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 for 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.
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We consider in depth the applicability of the Wiedemann-Franz (WF) law, namely that the electronic thermal conductivity ($kappa$) is proportional to the product of the absolute temperature ($T$) and the electrical conductivity ($sigma$) in a metal wi
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The Wiedemann-Franz law, connecting the electronic thermal conductivity to the electrical conductivity of a disordered metal, is generally found to be well satisfied even when electron-electron (e-e) interactions are strong. In ultra-clean conductors
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