Thermal transport mapping in twisted double bilayer graphene

Abstract: Two-dimensional (2D) materials have attracted significant interest due to their tunable physical properties when stacked into heterostructures. Twisting adjacent layers introduces moire patterns that strongly influence the material's electronic and thermal behavior. In twisted graphene systems, the twist angle critically alters phonon transport, leading to reduced thermal conductivity compared to Bernal-stacked configurations. However, experimental investigations into thermal transport in twisted structures remain limited. Here, we study the local thermal properties of twisted double bilayer graphene (TDBG) using Scanning Thermal Microscopy (SThM). We find a reduction in thermal resistance of 0.3 +/- 0.1 x 10^6 K W^-1 compared to untwisted bilayers, attributed to changes in both intrinsic thermal conductivity and the tip-sample interface. These results, supported by analytical modeling, provide new insight into thermal transport mechanisms in twisted 2D systems and offer a pathway toward thermal engineering in twistronic devices.