Anomalous enhancement of thermal conduction across twisted van der Waals heterointerfaces

Abstract

The advent of interlayer twist has introduced a groundbreaking paradigm, unveiling novel physical phenomena spanning from correlated insulating states to superconductivity. This unprecedented platform facilitates the manipulation of electrons and extends its capabilities to the effective control of bosons. For phonons, a consensus has been reached that interlayer twist greatly suppresses phonon transport as it breaks the symmetry of the lattice. Here, we report a counterintuitive experimental observation in which the interlayer twist can significantly promote the transportation of phonons across an intrinsically asymmetric heterointerface. Employing the time-domain thermoreflectance mapping technique, our results show a 2.5-fold increase in interfacial thermal conductance (ITC) in twisted bilayer MoS 2 /WS 2 heterostructures relative to initial commensurate configurations. Combined experimental and atomic simulation results reveal the inelastic scattering-dominated nature of thermal transport at MoS 2 /WS 2 heterointerfaces. The introduction of interlayer twist amplifies this effect, triggering a reconstruction of nonequilibrium phonon temperature distributions at the interface. This phenomenon activates efficient optical-to-acoustic phonon conversion through inelastic scattering and creates additional transport channels that overcome the intrinsic phonon mismatch in heterostructures. Our work establishes a paradigm for enhancing ITC by strategically introducing interlayer perturbations to amplify inelastic scattering effects. This breakthrough opens broad avenues for advanced thermal management in integrated circuits.