Study the optical properties of Pr2CuO4 thin films with different T c0 via spectroscopic ellipsometry
Abstract
In this work, we primarily present spectroscopic ellipsometry (SE) study on Pr2CuO4 (PCO) thin films, a parent compound of electron-doped cuprate superconductors. The c-aixs orientation films with various superconducting transition temperature Tc0 were prepared by a chemical method, which are single phase and good crystallinity verified by x-ray diffraction. The imaginary part of dielectric function (ɛi) of PCO was investigated by SE using a four-layer optical model in the photon energy range from 1.55 to 4.13 eV. Through fitting the second derivative spectra of ɛi via critical point model, we find that the charge-transfer gap exists in PCO system and, more importantly, this gap has a negative relationship with Tc0. This viewpoint demonstrates that the charge-transfer gap would merge together with the electrons doping in PCO and opens a door to understand the nature of cuprate superconductors.
- Publication:
-
Materials Research Express
- Pub Date:
- October 2019
- DOI:
- 10.1088/2053-1591/ab3941
- Bibcode:
- 2019MRE.....6j6416S
- Keywords:
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- Pr2CuO4;
- dielectric fuction;
- spectroscopic ellipsometry