Thermally driven ballistic rectifer

TL;DR

This paper investigates a four-terminal quasi-ballistic junction's response to thermal gradients, revealing a novel transverse thermovoltage and establishing a predictive model linking thermal and electrical responses.

Contribution

It introduces a four-terminal thermoelectric device with a central scattering site and develops a scattering model to predict thermal response from electrical behavior.

Findings

Discovery of a transverse thermovoltage in a four-terminal device

Model predicting thermal response from nonlinear electrical response

Foundation for future nonlocal thermoelectric device concepts

Abstract

The response of electric devices to an applied thermal gradient has, so far, been studied almost exclusively in two-terminal devices. Here we present measurements of the response to a thermal bias of a four-terminal, quasi-ballistic junction with a central scattering site. We find a novel transverse thermovoltage measured across isothermal contacts. Using a multi-terminal scattering model extended to the weakly non-linear voltage regime, we show that the device's response to a thermal bias can be predicted from its nonlinear response to an electric bias. Our approach forms a foundation for the discovery and understanding of advanced, nonlocal, thermoelectric phenomena that in the future may lead to novel thermoelectric device concepts.