Thermoelectric Efficiency in Nanojunctions: A Comparison between Atomic Junctions and Molecular Junctions

Thermoelectric efficiency in nanojunctions: a comparison between atomic junctions and molecular junctions.

Using first-principles approaches, we investigate the thermoelectric efficiency, characterized by the figure of merit ZT, in metallic atomic junctions and insulating molecular junctions. To gain insight into the properties of ZT, an analytical theory is also developed to study the dependence of ZT on lengths (l) and temperatures (T). The theory considers the combined heat current carried by ele...

Quantum interference in thermoelectric molecular junctions: A toy model perspective

Thermoelectric effects in nanoscale junctions.

Despite its intrinsic nonequilibrium origin, thermoelectricity in nanoscale systems is usually described within a static scattering approach which disregards the dynamical interaction with the thermal baths that maintain energy flow. Using the theory of open quantum systems, we show instead that unexpected properties, such as a resonant structure and large sign sensitivity, emerge if the nonequ...

Oligoyne Molecular Junctions for Efficient Room Temperature Thermoelectric Power Generation.

Understanding phonon transport at a molecular scale is fundamental to the development of high-performance thermoelectric materials for the conversion of waste heat into electricity. We have studied phonon and electron transport in alkane and oligoyne chains of various lengths and find that, due to the more rigid nature of the latter, the phonon thermal conductances of oligoynes are counterintui...

Nonlinear thermoelectric properties of molecular junctions with vibrational coupling

M. Leijnse,1 M. R. Wegewijs,2,3,4 and K. Flensberg1 1Nano-Science Center, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen Ø, Denmark 2Institut für Theoretische Physik A, RWTH Aachen, 52056 Aachen, Germany 3Institut für Festkörper-Forschung—Theorie 3, Forschungszentrum Jülich, 52425 Jülich, Germany 4JARA-Fundamentals of Future Information Technology Received 26 April 2010; revise...