High-energy optical transitions and optical constants of CH3NH3PbI3 measured by spectroscopic ellipsometry and spectrophotometry
| Autor: | Pavlos G. Lagoudakis, Giacomo Piana, Christopher G. Bailey |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
High energy
Materials science Analytical chemistry Halide FOS: Physical sciences 02 engineering and technology Applied Physics (physics.app-ph) 010402 general chemistry 01 natural sciences Metal Spectrophotometry medicine Physical and Theoretical Chemistry Condensed Matter - Materials Science Tandem medicine.diagnostic_test Materials Science (cond-mat.mtrl-sci) Physics - Applied Physics 021001 nanoscience & nanotechnology 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials General Energy visual_art visual_art.visual_art_medium Spectroscopic ellipsometry 0210 nano-technology |
| Popis: | Optoelectronics based on metal halide perovskites (MHPs) have shown substantial promise, following more than a decade of research. For prime routes of commercialization such as tandem solar cells, optical modeling is essential for engineering device architectures, which requires accurate optical data for the materials utilized. Additionally, a comprehensive understanding of the fundamental material properties is vital for simulating the operation of devices for design purposes. In this article, we use variable angle spectroscopic ellipsometry (SE) to determine the optical constants of CH$_3$NH$_3$PbI$_3$ (MAPbI$_3$) thin films over a photon energy range of 0.73 to 6.45 eV. We successfully model the ellipsometric data using six Tauc-Lorentz oscillators for three different incident angles. Following this, we use critical-point analysis of the complex dielectric constant to identify the well-known transitions at 1.58, 2.49, 3.36 eV, but also additional transitions at 4.63 and 5.88 eV, which are observed in both SE and spectrophotometry measurements. This work provides important information relating to optical transitions and band structure of MAPbI$_3$, which can assist in the development of potential applications of the material. 18 pages, 4 figures |
| Databáze: | OpenAIRE |
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