The effect of dopants on the dielectric constant of HfO[sub 2] and ZrO[sub 2] from first principles

2008 ◽  
Vol 92 (1) ◽  
pp. 012908 ◽  
Author(s):  
Dominik Fischer ◽  
Alfred Kersch
Keyword(s):  
Dielectric Constant ◽  
First Principles

Preliminary First Principles Study Of Hf and Zr Aluminates as Replacement High-k Dielectrics

2001 ◽  
Vol 670 ◽  
Author(s):  
Michael Haverty ◽  
Atsushi Kawamoto ◽  
Gyuchang Jun ◽  
Kyeongjae Cho ◽  
Robert Dutton
Keyword(s):  
Density Functional Theory ◽  
Dielectric Constant ◽  
Bulk Density ◽  
First Principles ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Conduction Band Edge ◽  
Functional Theory ◽  
Trade Off ◽  
High K

ABSTRACTBulk Density Functional Theory calculations were performed on Hf and Zr substitutions for Al in κ-alumina. The lowest energy configuration found was an octahedrally coordinated Zr site. Zr dissolution was favorable with an enthalpy of -2eV/unit cell for forming Al1.875Zr0.125O3 from pure Zr and κ-alumina. Hf and Zr substitution for Al atoms introduced empty d-states below the conduction band edge reducing the Eg of pure κ-alumina (7.5eV) to 6.4-5.9eV. The edge of the valence band however remained fixed by the O p-state character. The substitution of Hf and Zr into the alumina structure may lead to a higher dielectric constant, but will also reduce Eg and result in a trade off in tunneling currents in devices.

Phonons and static dielectric constant inCaTiO3from first principles

2000 ◽  
Vol 62 (6) ◽  
pp. 3735-3743 ◽  
Author(s):  
Eric Cockayne ◽  
Benjamin P. Burton
Keyword(s):  
Dielectric Constant ◽  
First Principles ◽  
Static Dielectric Constant

Tunable biaxial hyperbolic dispersion and negative refraction in graphite

2020 ◽  
Vol 34 (11) ◽  
pp. 2050110
Author(s):  
Hongya Wu ◽  
Jiayu Jia ◽  
Liang Xu ◽  
Ruoshan Zhou ◽  
Guoqiang Qin ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Optical Properties ◽  
First Principles ◽  
High Performance ◽  
Negative Refraction ◽  
Frequency Range ◽  
Hyperbolic Dispersion ◽  
Properties Of Materials ◽  
Optical Properties Of Materials ◽  
Significant Attention

In recent years, significant attention has been attracted to hyperbolic (or indefinite) materials resulting from their extraordinary optical properties, such as all-angle negative refraction. Here, tunable biaxial hyperbolic dispersion and negative refraction were found in graphite crystal. First principles were used to calculate the permittivity of graphite in [Formula: see text]-, [Formula: see text]- and [Formula: see text]-directions, the results indicate that graphite crystals exhibit indefinite dielectric constant tensor in certain frequency range. By adjusting strain, the optical properties of materials changed, and even switched from hyperbolic to elliptical materials in some frequency. This work demonstrates the feasibility of achieving high-performance tunable biaxial natural hyperbolic materials which can be used in various ways.

Nano-Scale Profile of the Dielectric Constant Near the Si/oxide Interface: A First-Principles Approach

2019 ◽  
Vol 11 (6) ◽  
pp. 173-182
Author(s):  
Jun Nakamura ◽  
Sadakazu Wakui ◽  
Shunsuke Eguchi ◽  
Ryosuke Yanai ◽  
Akiko Natori
Keyword(s):  
Dielectric Constant ◽  
First Principles ◽  
Oxide Interface ◽  
Nano Scale ◽  
Scale Profile

Computer Simulation of the Metal Silicide

2012 ◽  
Vol 170-173 ◽  
pp. 3367-3370
Author(s):  
Dong Chen ◽  
Chao Xu
Keyword(s):  
Dielectric Constant ◽  
First Principles ◽  
Plasma Frequency ◽  
Low Frequency ◽  
Potential Method ◽  
Frequency Region ◽  
Optical Parameters ◽  
Metal Silicide ◽  
Near Future ◽  
Pseudo Potential

We have investigated the optical properties of the Fm-3m-Mg2Si using the first-principles plane-wave pseudo-potential method. Some important optical parameters (reflectivity, refractive index, extinction coefficient, loss function and dielectric function) are calculated and investigated at high pressure. The calculated static dielectric constant ε(0) is 15.9. The computed plasma frequency is 12eV. Some interesting features in the optical parameters are found in the low frequency region. Nevertheless, the calculated result needs to be testified by experiments in the near future.

Calculation of the Stability and the Polarizability of Isolated Fullerene Molecules as a Function of Charge State

1992 ◽  
Vol 270 ◽  
Author(s):  
Andrew A. Quong ◽  
Mark R. Pederson
Keyword(s):  
Dielectric Constant ◽  
Electronic Structure ◽  
Simple Model ◽  
First Principles ◽  
Density Functional Calculations ◽  
Density Functional ◽  
Local Density ◽  
Neutral Molecule ◽  
Local Density Functional ◽  
The Stability

ABSTRACTWe present first-principles local density functional calculations of the electronic structure and energetics of neutral and negatively charged fullerene molecules. We find thatthe negatively charged -1 state is stable relative to the neutral molecule and that the -2 state is stable relative to the neutral molecule but not to the -1 state of the molecule. We have also performed calculations of the electronic polarizabilities for different charged states and developed a simple model to estimate the dielectric constant of fullerene based crystals.

Sign in / Sign up

Export Citation Format

Share Document