Heat Flow Guiding and Modulation by Kinks in a Silicon Nanoribbon

Tailoring heat flow in solids has profound implications for the innovation of functional thermal devices. However, the current methods face technological challenges related to system complexity, material stability, and operating temperature. In this study, we demonstrated efficient heat flow modulation in a single material without a phase transition, using a simple and entirely material-independent strategy, kinked nanostructure patterning, at near-ambient temperature. By carefully controlling the kink arm length and kink angle of the Si nanoribbons, we achieved a thermal conductivity modulation of up to similar to 20%. Our theoretical modeling showed that this modulation results from the competing roles of phonon backscattering and open view channels on heat transport. We also build a regime map based on the existence of an open view channel and provide concrete design guidelines for thermal conductivity modulation considering the kink angle and arm length. This study opens up new opportunities for efficient heat flow manipulation through nanostructure patterning.

Automated summary

In this study, efficient heat flow modulation in a single material was achieved without a phase transition, using a simple and material-independent strategy of kinked nanostructure patterning at near-ambient temperature. The modulation was achieved by controlling the kink arm length and angle of Si nanoribbons, resulting from the competing roles of phonon backscattering and open view channels on heat transport. This study opens up new opportunities for efficient heat flow manipulation through nanostructure patterning.