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We characterize the response of isolated single-wall (SWNT) and multiwall (MWNT) carbon nanotubes and nanotube bundles to static electric fields using first-principles calculations and density-functional theory. The longitudinal polarizability of SWNTs sca ...
We present a numerical study of the tunability properties of a plasmonic subwavelength particle deposited on a metallic slab. The particle is composed of a metallic part, supporting a localized plasmon mode, separated from the slab by a dielectric spacer. ...
Models of amorphous (HfO2)x(SiO2)(1), for varying hafnium, content x are generated by ab initio molecular dynamics. The structural properties are analyzed in terms of pair distribution functions from which typical bond lengths and coordination numbers are ...
Electronic band gaps and dielectric constants are obtained for amorphous hafnium silicates using first-principles methods. Models of amorphous (HfO2)(x)(SiO2)(1-x) for varying x are generated by ab initio molecular dynamics. The calculations show that the ...
The dielectric response of a ferroelectric film with bilinear coupling between order parameter and strain is theoretically addressed. An exact solution for the total (lattice and domain contributions) dielectric permittivity of the system for the case wher ...
BaxSr1-xTiO3 (BST) and its composite films have been studied for the improvement of the tunable performances via nano-structual control. The strong correlation between strain and tunability similar to that between strain and permittivity was confirmed in t ...
The dielectric response of ferroelectric-dielectric composites is theoretically addressed. Dielectric permittivity, tunability (relative change of the permittivity driven by dc electric field), and loss tangent are evaluated for various composite models. T ...
The presence of free charges and numerous discontinuities separating liquid, gas, and solid phases in partially saturated soils give rise to Maxwell-Wagner polarization that may significantly affect bulk dielectric permittivity measurements. Evidence sugge ...
We study the infrared properties of the Si-SiO2 interface within a first-principles approach. In order to provide an atomic-scale description of the dielectric permittivity (both high-frequency and static) and of the infrared absorption at the interface, w ...
We study the electronic structure and the dielectric permittivity of ultrathin oxide layers on Si(I 00) substrates. By considering two different Si(l 00)-SiO2 interface models, we first show that the electronic structure in the interfacial oxide differs fr ...
