Comment on: A significant enhancement in visible-light photodetection properties of chemical spray pyrolysis fabricated CdS thin films by novel Eu doping concentrations [Sens. Actuator. A Phys. 301 (2020) 111749]

TL;DR

This paper critiques a recent study on Eu-doped CdS thin films, highlighting errors in optical property calculations due to incorrect refractive index equations, which affect the reported optical characteristics.

Contribution

It provides a critical analysis of the previous work, emphasizing the importance of correct equations for accurate optical property determination in thin films.

Findings

Incorrect refractive index equations led to wrong optical property values

The optical parameters such as dielectric constant and nonlinear refractive index were inaccurately reported

Highlights the need for proper methodology in optical property calculations

Abstract

In a recent paper [Sens. Actuator. A Phys. 301 (2020) 111749] Shkir et al. have studied the structural, optical and photo-electrical properties of the CdS thin films as a function of Eu doping concentration. The authors have used a wrong equation to calculate the refractive index and obtained values are incorrect. Consequently, the optical properties obtained based on the refractive index such as real and imaginary parts of dielectric constant, dielectric loss, optical conductivity, nonlinear refractive index (n2), linear and third-order non-linear optical susceptibility are wrong.