Tunable Thermal Switching via DNA-Based Nano Devices

TL;DR

This paper demonstrates that DNA's structural transition can be harnessed to create nano-scale thermal switches with tunable conductance, driven by denaturation and sequence variations.

Contribution

It introduces DNA-based nanojunctions as tunable thermal devices exploiting denaturation-induced conductance changes and nonlinear effects.

Findings

Thermal conductance increases rapidly across DNA denaturation transition.

Sequence and length variations enable broad thermal tunability.

Disorder influences thermal properties and relates to genomic DNA.

Abstract

DNA has a well-defined structural transition -- the denaturation of its double-stranded form into two single strands -- that strongly affects its thermal transport properties. We show that, according to a widely implemented model for DNA denaturation, one can engineer DNA "heattronic" devices that have a rapidly increasing thermal conductance over a narrow temperature range across the denaturation transition (~350 K). The origin of this rapid increase of conductance, or "switching", is the softening of the lattice and suppression of nonlinear effects as the temperature crosses the transition temperature and DNA denatures. Most importantly, we demonstrate that DNA nanojunctions have a broad range of thermal tunability due to varying the sequence and length, and exploiting the underlying nonlinear behavior. We discuss the role of disorder in the base sequence, as well as the relation to genomic DNA. These results set the basis for developing thermal devices out of materials with nonlinear structural dynamics, as well as understanding the underlying mechanisms of DNA denaturation.