Local rectification of heat flux

TL;DR

This paper introduces a simple one-dimensional chain model demonstrating heat flux rectification solely through a localized impurity, without requiring material grading or long-range interactions, highlighting a new minimal mechanism for thermal diode behavior.

Contribution

The study presents a minimal homogeneous chain model with a single impurity that achieves heat flux rectification, independent of complex material interfaces or long-range forces.

Findings

Heat flux is asymmetric due to a localized impurity.

Rectification persists with linear interactions except at the impurity.

The mechanism does not depend on material grading or long-range forces.

Abstract

We present a chain-of-atoms model where heat is rectified, with different fluxes from the hot to the cold baths located at the chain boundaries when the temperature bias is reversed. The chain is homogeneous except for boundary effects and a local modification of the interactions at one site, the "impurity". The rectification mechanism is due here to the localized impurity, the only asymmetrical element of the structure, apart from the externally imposed temperature bias, and does not rely on putting in contact different materials or other known mechanisms such as grading or long-range interactions. The effect survives if all interaction forces are linear except the ones for the impurity.