Seebeck Coefficient of AuxGe1−x Thin Films Close to the Metal-Insulator Transition for Molecular Junctions

Abstract

The Au${}_{x}$Ge${}_{1\ensuremath{-}x}$ alloy in the thin-film limit is an interesting material for nanoscale thermoelectric applications, particularly close to its metal-insulator transition, which occurs for $x$ around18--20%. This study presents a detailed characterization of this system, revealing good properties for thermal sensing. This alloy's unexpectedly low Seebeck coefficient combined with its resistive behavior as a function of temperature makes it particularly apt for use as a local heater and thermometer. Moreover, the work demonstrates the ability to integrate this thin film as an electrode in large-area junctions based on ultrathin molecular layers.