Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Effect of Oxygen Stoichiometry on the Magnetization Profiles and Negative Magnetization in LSMO Thin Films

Published

Author(s)

Robbyn Trappen, Alexander J Grutter, Chih-Yeh Huang, Aubrey Penn, Navid Mottaghi, Saeed Yousefi, Allison Haertter, Shalini Kumari, James LeBeau, Brian J Kirby, Mikel B. Holcomb

Abstract

The depth dependent magnetization in thin film oxygen stoichiometric and oxygen deficient La0.7Sr0.3MnO3 is investigated by using polarized neutron reflectivity. The stoichiometric sample shows enhanced interfacial magnetization relative to the rest of the film. The oxygen deficient sample exhibits a reduced average magnetization from the optimized recipe. Both films show regions of suppressed magnetization at the surface regardless of growth pressure. The oxygen stoichiometric film does not show an interfacial dead layer whereas the oxygen deficient film exhibits a dead layer whose thickness changes with temperature. At low applied field we observe striking differences in the depth dependence of the magnetic ordering, with the oxygen deficient film exhibiting exchange-spring behavior, while the stoichiometric film shows a constant magnetization direction across the film. These results suggest that the incorporation of oxygen vacancies during growth leads to an accumulation of vacancies at the interface which is enhanced at higher temperature due to increased oxygen mobility, creating a region of reduced magnetism which couples to the rest of the film. These results offer insight into the complex behavior and role of oxygen vacancies in the magnetism of these systems. Additionally, the study reveals further details of the negative magnetization in La0.7Sr0.3MnO3 reported in previous studies which are discussed here.
Citation
Journal of Applied Physics
Volume
126
Issue
10

Keywords

Magnetism, interface, oxide, film, perovskite, neutron reflectometry

Citation

Trappen, R. , , A. , Huang, C. , Penn, A. , Mottaghi, N. , Yousefi, S. , Haertter, A. , Kumari, S. , LeBeau, J. , , B. and , M. (2019), Effect of Oxygen Stoichiometry on the Magnetization Profiles and Negative Magnetization in LSMO Thin Films, Journal of Applied Physics, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=928233 (Accessed August 1, 2021)
Created September 13, 2019, Updated September 11, 2020