The impact of iron concentration on strontium titanate oxide materials as shown through ultrafast dynamics

Understanding the ultrafast dynamics of photo-ionic materials such as Sr(Ti1-xFex)O3-x/2+δ will allow for the development of design principles of future photo-ionic materials. Optical transient absorption on a sub picosecond to few nanosecond timescale was performed on a series of different iron content in Sr(Ti1-xFex)O3-x/2+δ. Several experimental parameters had to be checked in order to get the most accurate excited state spectra. These included the fluence of the light, the wavelength of excitation, and samples prepared in different ways. After evaluating each of these conditions, excited state spectra of six samples ranging from an iron content of 4% to 35% were studied with an excitation wavelength of 340 nm and a fluence of 0.7 mJ/cm2. The excited state spectra of the series differs qualitatively between the low vs high iron content. All of the excited state spectra show features from band gap renormalization and free carrier absorption. On the timescale studied in this experiment, longer lived excited states are correlated with lower iron content.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Chemistry

Grantor

University of Illinois Urbana-Champaign

Year dc:date

2025

Author dc:creator

• Schueller, Kailyn Marie

Contributors dc:contributor

• Vura-Weis, Josh A.

• Photo-ionics
• Ultrafast Spectroscopy

Statement dc:rights

• Copyright 2025 Kailyn Schueller

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/129638

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F129638