Department of Applied Physics and Materials Science - Materials Science

Materials Science Research Lecture

Wednesday April 10, 2019 4:00 PM

Nanophononic Devices Based on Layered Materials

Speaker: Davide Donadio, Chemistry, UC Davis
Location: Spalding Laboratory 106 (Hartley Memorial Seminar Room)

Abstract:

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 quasi-ballistic 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 low-dimensional materials and devices, including graphene, molecular junctions and ultrathin silicon membranes. In particular our work aids a microscopic interpretation of recent experimental measurements of multilayer graphene junctions and of 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.

More about the Speaker:

Davide Donadio is a theoretical materials scientist. He earned his Ph.D. in 2003 at the University of Milan, with a work that featured electronic structure calculations and molecular dynamics simulations of silicate glasses. He then moved to ETH Zurich (Prof. Parrinello's group), where he studied materials at extreme conditions and crystal nucleation. In 2007 he joined Prof. Galli's group at UC Davis and worked on nanoscale heat transport in thermoelectrics.

From 2010 to 2015 he lead the Max Planck Research Group for "Theory of nanostructures" at the MPI for Polymer Research in Mainz (Germany), investigating non-equilibrium processes at the nanoscale by molecular simulations. In 2014 he was appointed Ikerbasque professor at DIPC (Donostia, Spain), and he then moved to UC Davis, where he continues his research activity on crystallization, surface chemistry, and nanophononics. He has published 108 peer-reviewed articles and three book chapters.

Series Materials Research Lecture Series

Contact: Jennifer Blankenship at 626-395-8124 jennifer@caltech.edu