Nonlinear alternating current responses of graded materials
Abstract
When a composite of nonlinear particles suspended in a host medium is subjected to a sinusoidal electric field, the electrical response in the composite will generally consist of alternating current (AC) fields at frequencies of higher-order harmonics. The situation becomes more interesting when the suspended particles are graded, with a spatial variation in the dielectric properties. The local electric field inside the graded particles can be calculated by the differential effective dipole approximation, which agrees very well with a first-principles approach. In this work, a nonlinear differential effective dipole approximation and a perturbation expansion method have been employed to investigate the effect of gradation on the nonlinear AC responses of these composites. The results showed that the fundamental and third-harmonic AC responses are sensitive to the dielectric-constant and/or nonlinear-susceptibility gradation profiles within the particles. Thus, by measuring the AC responses of the graded composites, it is possible to perform a real-time monitoring of the fabrication process of the gradation profiles within the graded particles.
Cite
@article{arxiv.cond-mat/0310593,
title = {Nonlinear alternating current responses of graded materials},
author = {J. P. Huang and L. Gao and K. W. Yu and G. Q. Gu},
journal= {arXiv preprint arXiv:cond-mat/0310593},
year = {2007}
}
Comments
18 pages, 4 figures