Broadband dielectric spectroscopy on single-crystalline and ceramic CaCu3Ti4O12

TL;DR

This study investigates the dielectric properties of CaCu3Ti4O12 across a broad frequency range, comparing single crystals and ceramics, and explores the second relaxation phenomenon in both forms.

Contribution

It provides new dielectric measurements up to 1.3 GHz on single crystals and offers a method to achieve high dielectric constants in polycrystals.

Findings

Detection of the second relaxation in single crystals.

Comparable dielectric constants in polycrystals and single crystals with proper processing.

Extension of dielectric measurements up to 1.3 GHz.

Abstract

We present dielectric measurements of the colossal dielectric constant material CaCu3Ti4O12 extending up to 1.3 GHz also covering so far only rarely investigated single crystalline samples. Special emphasis is put on the second relaxation reported in several works on polycrystals, which we detect also in single crystals. For polycrystalline samples we provide a recipe to achieve values of the dielectric constant as high as in single crystals.