Epitaxial Thin Films of the Giant-Dielectric-Constant Material CaCu_3Ti_4O_{12} Grown by Pulsed-laser Deposition

TL;DR

This paper reports the successful growth of epitaxial thin films of CaCu_3Ti_4O_{12} with giant dielectric constants using pulsed-laser deposition, highlighting their temperature stability and potential for applications.

Contribution

It demonstrates the fabrication of epitaxial CaCu_3Ti_4O_{12} thin films with stable giant dielectric constants on various substrates, expanding their practical use.

Findings

Dielectric constant ~1500 over wide temperature range

Temperature independence of dielectric constant above 150K

Activated relaxation process below 150K

Abstract

Pulsed-laser deposition has been used to grow epitaxial thin films of the giant-dielectric-constant material CaCu_3Ti_4O_{12} on LaAlO_3 and SrTiO_3 substrates with or without various conducting buffer layers. The latter include YBa_2Cu_3O_7, La_{1.85}Sr_{0.15}CuO_{4+\delta} and LaNiO_3. Above 100K - 150K the thin films have a temperature independent dielectric constant as do single crystals. The value of the dielectric constant is of the order of 1500 over a wide temperature region, potentially making it a good candidate for many applications. The frequency dependence of its dielectric properties below 100K - 150K indicates an activated relaxation process.