Optical properties of strontium titanate (STO) thin films using transfer matrix method

The transfer matrix method is a very effective theoretical technique investigating the optical properties of a single and layered thin films. By utilizing the transfer matrix method, the transmission, reflection, and absorption properties of Strontium Titanate (STO) thin films are analyzed across a wide range of wavelengths. For 250 nm and 260 nm thick STO thin films, the optical direct band gaps 3.49 eV and 3.59 eV respectively are found to be consistent with the experimental findings. Additionally, the impact of film thickness and optical band gap on response of STO thin films is explored. It is noticed that with the increase in thickness of thin film, the band gap is redshifted and its value is increased as well. The findings presented in this paper contribute to a comprehensive understanding of the optical behavior of STO thin films, enabling further advancements in the design and fabrication of STO-based optoelectronic devices.