Optical absorption in epitaxial La{sub 1-x}Sr{sub x}FeO{sub 3} thin films

• Published in: Applied physics letters Vol. 102; no. 8
• Main Authors: Scafetta, M D., Xie, Y. J., Torres, M., Spanier, J. E., May, S. J.
• Format: Journal Article
• Language: English
• Published: United States 25-02-2013
• Subjects: ABSORPTION; ABSORPTION SPECTRA; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CRYSTAL GROWTH; DEPOSITS; FERRITES; LANTHANUM COMPOUNDS; LAYERS; MOLECULAR BEAM EPITAXY; OXIDES; PEROVSKITE; RED SHIFT; STRAINS; STRONTIUM COMPOUNDS; STRONTIUM TITANATES; SUBSTRATES; THIN FILMS
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4794145

We report the dependence of optical absorption on Sr concentration in La{sub 1-x}Sr{sub x}FeO{sub 3} (LSFO) (x{<=}0.4) perovskite thin films. Strained epitaxial films were deposited on SrTiO{sub 3} substrates using oxide molecular beam epitaxy. We find systematic changes in the optical absorption spectra with increasing x including a red-shift of transition energies and the increasing presence of a lower energy transition within the fundamental gap of pure LaFeO{sub 3}. These results serve as a demonstration of the complex manner in which absorption spectra can be altered in complex oxides via heterovalent A-site substitution.