Majidi Danial, Josefsson Martin, Kumar Mukesh, Leijnse Martin, Samuelson Lars, Courtois Hervé, Winkelmann Clemens B, Maisi Ville F
Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, 25 rue des Martyrs, 38042 Grenoble, France.
NanoLund and Solid State Physics, Lund University, Box 118, 22100 Lund, Sweden.
Nano Lett. 2022 Jan 26;22(2):630-635. doi: 10.1021/acs.nanolett.1c03437. Epub 2022 Jan 14.
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.
维德曼-夫兰兹定律表明，电荷电导与电子对热导率的贡献成正比。这对热电应用的效率界限提出了严格限制，热电应用旨在以小热流响应实现大电荷传导。我们展示了基于在半导体砷化铟纳米线晶体管内部形成的量子点的实验，其中热导率可被显著调节至低于维德曼-夫兰兹预测值。与散射理论的比较表明，这是由量子限制以及量子点由此产生的能量选择性输运特性所致。我们的结果为在半导体纳米结构中独立定制热传导和电传导特性开辟了前景。
