Thermoelectric effects at a Germanium-electrolyte interface: measuring 100 nK temperature oscillations at room temperature

TL;DR

This paper reports the measurement of extremely small temperature oscillations at a Germanium-electrolyte interface at room temperature, revealing thermoelectric effects and proposing a new method to study molecular-scale dissipation phenomena.

Contribution

It introduces a novel measurement technique for nanoscale thermoelectric effects at a complex interface, linking the Debye layer behavior to transmission line dynamics.

Findings

Detection of 100 nK temperature oscillations at room temperature.

Identification of thermoelectric heat deposition at the interface.

Modeling the Debye layer as a low frequency transmission line.

Abstract

We describe measurements of 100 nK temperature oscillations at room temperature, driven at the complex interface between p-doped Germanium, a nm size metal layer, and an electrolyte. We show that heat is deposited at this interface by thermoelectric effects, however the precise microscopic mechanism remains to be established. The temperature measurement is accomplished by observing the modulation of black body radiation from the interface. We argue that this geometry offers a method to study molecular scale dissipation phenomena. The Debye layer on the electrolyte side of the interface controls much of the dynamics. Interpreting the measurements from first principles, we show that in this geometry the Debye layer behaves like a low frequency transmission line.