Ultrahigh Thermal Conductance across Superlubric Interfaces in Twisted Graphite.

Interlayer rotation in van der Waals (vdW) materials offers a unique degree of freedom for manipulating lattice dynamics and leads to an exotic state with vanishing friction called structural superlubricity. Extensive theoretical calculations have also predicted the potential of twisted vdW materials for controlling heat flow in advanced electronics. However, precise experimental measurements have proven extremely challenging with only a handful of efforts to date reporting inconsistent results. Here, we have managed to achieve simultaneous mechanical characterizations and thermal measurements of the intrinsic twisted interfaces in microfabricated graphite mesas. Remarkably, the conductance of superlubric interfaces reaches about 600  MWm^{-2} K^{-1} which surpasses the measured values for artificially stacked vdW structures by nearly an order of magnitude. Nonetheless, we successfully resolved over 30-fold variation of thermal conductance as the buried interfaces were rotated to a locked state. Further, atomic simulations revealed the predominant role of the transverse acoustic phonons. Together, our findings highlight a general physical picture that directly correlates interfacial thermal transport with sliding resistance, and lay the foundation for twist-enabled thermal management which are particularly beneficial to twistronics and slidetronics.