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arXiv · 1110.0352

Lineshape of the thermopower of quantum dots

S. Fahlvik Svensson·A. I. Persson·E. A. Hoffmann·N. Nakpathomkun·H. A. Nilsson·H. Q. Xu·L. Samuelson·H. Linke
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Abstract

Quantum dots are an important model system for thermoelectric phenomena, and may be used to enhance the thermal-to-electric energy conversion efficiency in functional materials. It is therefore important to obtain a detailed understanding of a quantum-dot's thermopower as a function of the Fermi energy. However, so far it has proven difficult to take effects of co-tunnelling into account in the interpretation of experimental data. Here we show that a single-electron tunnelling model, using knowledge of the dot's electrical conductance which in fact includes all-order co-tunneling effects, predicts the thermopower of quantum dots as a function of the relevant energy scales, in very good agreement with experiment.

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S. Fahlvik Svensson, A. I. Persson, E. A. Hoffmann, N. Nakpathomkun, H. A. Nilsson, H. Q. Xu, L. Samuelson, H. Linke. 2011-10-03. Lineshape of the thermopower of quantum dots. https://doi.org/10.1088/1367-2630/14/3/033041

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