[en] Using Monte Carlo simulations, we investigate the electrical conductivity of networks of hard rods with aspect ratios 10 and 20 as a function of the volume fraction for two tunneling conductance models. For a simple, orientationally independent tunneling model, we observe nonmonotonic behavior of the bulk conductivity as a function of volume fraction at the isotropic-nematic transition. However, this effect is lost if one allows for anisotropic tunneling. The relative conductivity enhancement increases exponentially with volume fraction in the nematic phase. Moreover, we observe that the orientational ordering of the rods in the nematic phase induces an anisotropy in the conductivity, i.e., enhanced values in the direction of the nematic director field. We also compute the mesh number of the Kirchhoff network, which turns out to be a simple alternative to the computationally expensive conductivity of large systems in order to get a qualitative estimate.
Disciplines :
Physics
Author, co-author :
Atashpendar, Arshia; Universität Freiburg
Arora, Sarthak
Rahm, Alexander ; University of Luxembourg > Faculty of Science, Technology and Communication (FSTC) > Mathematics Research Unit
Schilling, Tanja; Universität Freiburg
External co-authors :
yes
Language :
English
Title :
Simulation study of the electrical tunneling network conductivity of suspensions of hard spherocylinders
Publication date :
18 December 2018
Journal title :
Physical Review. E
ISSN :
2470-0053
Publisher :
American Physical Society, Ridge, United States - New York
Volume :
98
Pages :
062611
Peer reviewed :
Peer Reviewed verified by ORBi
Focus Area :
Physics and Materials Science
Funders :
Université du Luxembourg through Gabor Wiese’s AMFOR grant; The state of Baden-Württemberg through bwHPC and the German Research Foundation (DFG) through grant no INST 39/963-1 FUGG.