Exploring the universality of the alternating conductivity of disordered materials using the Gaussian distribution of activation energies.

Nenhuma Miniatura disponível
Data
2019
Título da Revista
ISSN da Revista
Título de Volume
Editor
Resumo
This paper presents a newapproach for the analysis of ACconductivity, s*(w)= s¢(w)+is(w), in disordered solids which brings together the quasi-universal frequency-dependent conductivity and the idea of a Gaussian distributions of probable activation energy barriers for hopping carriers. An explicit expression forAC conductivity was obtained using a complex dielectric response function and a continuous time random walk treatment applied to a lattice obeying the Kubo’s fluctuationdissipation theorem. This expression provides an insight into the universality of the form s¢(w) μ ws (0  s  1) and s(w) μ kw (k is the dielectric constant), aswell into the effect of the Gaussian disorder on exponent s.We discuss the similarities and differences with the Random Free Energy Barrier model equivalent to the long-used box model, and it brings support to an extending expression proposed by JCDyre and one of the authors. The applicability of the model to experimental observations on poly[(2-methoxy-5-hexyloxy)-p-phenylenevinylene] reveals the dielectric constant, mean energy and variance of the Gaussian distribution for hopping carriers in this disordered conjugated polymer.
Descrição
Palavras-chave
Hopping transport, Organic semiconductors, Conductivity phenomena in semiconductor
Citação
COUTO, J. D.; SANTOS, M. de C.; BIANCHI, R. F. Exploring the universality of the alternating conductivity of disordered materials using the Gaussian distribution of activation energies. Materials Research Express, v. 6, n. 4, p. 1-8, 2019. Disponível em: <https://iopscience.iop.org/article/10.1088/2053-1591/aad1ce>. Acesso em: 19 mar. 2019.