New Method for Reliable and Efficient Calculations of Resistivity & Mobility

Posted on August 21, 2017

A new paper using QuantumATK has been published in Phys. Rev. B [1] as a product of collaboration between Synopsys QuantumATK group and a group of researchers at the Technical University of Denmark. The paper presents a new method, MD-Landauer, combining Green's function transport and molecular dynamics (MD) for reliable and efficient calculations of resistivity and mobility including the effect of electron-phonon couplings (EPCs), which plays a central role in the performance of most electronic devices.

The MD-Landauer approach is validated against experimental results and state-of-the-art calculations using the Boltzmann Transport Equation (BTE) method [2] for a variety of systems: Si and Au nanowires, Si and Au bulk, Carbon Nano Tubes (CNTs) and graphene (see Fig 1). The calculated mobilities and resistivities agree semi-quantitatively with those calculated using the BTE method and with experiments, and trends are correctly reproduced. This shows that the MD-Landauer method is an appealing alternative to BTE to treat EPCs in large and complex (for example, non-crystalline, with defects and substitutions) systems. Full-scale Density Functional Theory electron-phonon calculations are just starting to become available as a method, and the MD-Landauer approach makes them much more reasonable in terms of computation time.