Who: Davide Donadio, University of California Davis
Place: Donostia International Physics Center
Date: Tuesday, 18 June 2019, 12:00
Devices enabling thermal rectification and dynamic control of nanoscale heat transport would be game changers in nanoelectronics and renewable energy harvesting. Two-dimensional van der Waals layered materials feature intriguing thermal transport properties and have been proposed as promising candidates to engineer thermal diodes, switches and transistors. However, several details of heat transport in these materials still need to be uncovered both in the bulk diffusive regime and in the nanoscale regime.
Using a multiscale approach, encompassing large-scale molecular dynamics, lattice dynamics simulations and ab initio calculations, we explored the microscopic mechanisms of heat transport various two-dimensional materials and device. Specifically, our quantum mechanical phonon calculations provide a microscopic interpretation of recent measurements of high thermal resistance multilayer graphene junctions. Furthermore, we address quasi-ballistic phonon transport regime in pure and lithium-intercalated molybdenum disulphide. We show that lithium intercalation and strain enable a large dynamical tuning of the thermal conductivity both in-plane and cross-plane. This property can be exploited to realize electrochemical thermal transistors with reversible modulation of the thermal conductance over a factor 10X.
Host: Ion Errea