Molecular Dynamics Simulations of Low-dimensional Materials: Accurate Force Field Generation and Investigation of Phononic Properties

Date: 4 April 2019

Venue: UAntwerpen, Campus Groenenborger, G.U. 204 - Groenenborgerlaan 171 - 2020 Antwerpen (route: UAntwerpen, Campus Groenenborger)

Time: 11:00 AM - 12:00 PM

Organization / co-organization: CMT

Short description: Condensed Matter Seminar presented by Dr Cem Sevik, Eskisehir Technical University, Turkey

Abstract
Recent advances in the synthesis of layered nanostructures, similar to graphene and hexagonal boron-nitride have led to significant interest in the characterization of these materials. In addition to the electronic and optical properties, thermal transport properties of these materials due to its crucial role in high-technological applications, have been extensively investigated with several different approaches.

Besides the first-principles based methods, molecular dynamics simulations, possessing undeniable advantages in the characterization of large-scale systems in particular with a disorder such as defects and grain boundaries, have been also favored by researchers. The applications have clearly demonstrated that this fully-anharmonic classical approach has the potential to characterize thermal transport properties of layered structures when compared with the other approaches and available experimental data. However, the direct dependency of its performance to the proper application of the method chosen to characterize the thermal transport properties and the accuracy of the force-field used have also arisen as a result of distinctive simulations.

In recent years, we have also performed systematic simulations in order to investigate the thermal transport properties of different two-dimensional materials such as hexagonal-BN, MoS2, and WSe2. We have generated accurate interatomic force-fields such as Tersoff and Stillinger-Weber types by utilizing novel stochastic search algorithms such as particle swarm optimization. Also, we have applied different approaches, i.e Green-Kubo, and Spectral Energy Density, in order to investigate thermal transport properties and effect of disorders on these properties. As a result, we have gained extensive experience in classical molecular dynamics simulations leading to the accurate determination of thermal transport properties of, particularly disordered two-dimensional structures. In this talk, we will share our insights gained over the years on this very promising research field.



Contact email: lucian.covaci@uantwerpen.be

Link: http://cmt.uantwerpen.be