Frequency Dependence of the Dielectric Constants and of the Reflectivity for HfO2 and ZrO2 from First-Principles Calculations

TL;DR

This study uses first-principles calculations to analyze how phonon dispersions influence the frequency-dependent dielectric properties and reflectivity of monoclinic ZrO2 and HfO2, highlighting lattice effects and pressure dependence.

Contribution

It provides theoretical insights into the frequency dependence of dielectric constants and reflectivity of ZrO2 and HfO2, emphasizing lattice contributions and anisotropy.

Findings

Lattice contributions are crucial for static dielectric constant evaluation.

Dielectric constants decrease with increasing pressure.

Anisotropy exists along x and z directions.

Abstract

We present, in this work, our theoretical results for the phonon dispersions and the frequency dependence of the reflectivities and the dielectric constants of ZrO2 and HfO2 in the monoclinic phase. The results show the importance of the lattice contribution for the evaluation of the static dielectric constant. Also, besides the anisotropy shown by these materials along the x and z directions, the zero frequency static dielectric constant decreases with the increasing pressure.